155403881 has 2 divisors, whose sum is σ = 155403882. Its totient is φ = 155403880.

The previous prime is 155403841. The next prime is 155403883. The reversal of 155403881 is 188304551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 142587481 + 12816400 = 11941^2 + 3580^2 .

It is a cyclic number.

It is not a de Polignac number, because 155403881 - 2¹⁰ = 155402857 is a prime.

It is a super-2 number, since 2×155403881² = 48300732459724322, which contains 22 as substring.

Together with 155403883, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (155403883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77701940 + 77701941.

It is an arithmetic number, because the mean of its divisors is an integer number (77701941).

Almost surely, 2^155403881 is an apocalyptic number.

It is an amenable number.

155403881 is a deficient number, since it is larger than the sum of its proper divisors (1).

155403881 is an equidigital number, since it uses as much as digits as its factorization.

155403881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19200, while the sum is 35.

The square root of 155403881 is about 12466.1092968095. The cubic root of 155403881 is about 537.6346946371.

The spelling of 155403881 in words is "one hundred fifty-five million, four hundred three thousand, eight hundred eighty-one".