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168668881 is a prime number
BaseRepresentation
bin10100000110110…
…10111011010001
3102202101021012121
422003122323101
5321134401011
624423054241
74115443003
oct1203327321
9382337177
10168668881
1187233477
12485a1381
1328c37494
1418588373
15ec1ae71
hexa0daed1

168668881 has 2 divisors, whose sum is σ = 168668882. Its totient is φ = 168668880.

The previous prime is 168668879. The next prime is 168668891. The reversal of 168668881 is 188866861.

168668881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 167961600 + 707281 = 12960^2 + 841^2 .

It is an emirp because it is prime and its reverse (188866861) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 188899891 and 198998881.

It is a cyclic number.

It is not a de Polignac number, because 168668881 - 21 = 168668879 is a prime.

It is a super-2 number, since 2×1686688812 = 56898382835584322, which contains 22 as substring.

Together with 168668879, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (168668891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84334440 + 84334441.

It is an arithmetic number, because the mean of its divisors is an integer number (84334441).

Almost surely, 2168668881 is an apocalyptic number.

It is an amenable number.

168668881 is a deficient number, since it is larger than the sum of its proper divisors (1).

168668881 is an equidigital number, since it uses as much as digits as its factorization.

168668881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 884736, while the sum is 52.

The square root of 168668881 is about 12987.2584096876. The cubic root of 168668881 is about 552.5161639518.

The spelling of 168668881 in words is "one hundred sixty-eight million, six hundred sixty-eight thousand, eight hundred eighty-one".