102209881 has 2 divisors, whose sum is σ = 102209882. Its totient is φ = 102209880.

The previous prime is 102209801. The next prime is 102209893. The reversal of 102209881 is 188902201.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 93915481 + 8294400 = 9691^2 + 2880^2 .

It is a cyclic number.

It is not a de Polignac number, because 102209881 - 2¹⁹ = 101685593 is a prime.

It is a super-2 number, since 2×102209881² = 20893719548068322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (102209801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51104940 + 51104941.

It is an arithmetic number, because the mean of its divisors is an integer number (51104941).

Almost surely, 2^102209881 is an apocalyptic number.

It is an amenable number.

102209881 is a deficient number, since it is larger than the sum of its proper divisors (1).

102209881 is an equidigital number, since it uses as much as digits as its factorization.

102209881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 102209881 is about 10109.8902565755. The cubic root of 102209881 is about 467.5531215909.

The spelling of 102209881 in words is "one hundred two million, two hundred nine thousand, eight hundred eighty-one".