2155508257 has 48 divisors (see below), whose sum is σ = 2703697920. Its totient is φ = 1681966944.

The previous prime is 2155508249. The next prime is 2155508263. The reversal of 2155508257 is 7528055512.

It is not a de Polignac number, because 2155508257 - 2³ = 2155508249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2155502257) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9018744 + ... + 9018982.

It is an arithmetic number, because the mean of its divisors is an integer number (56327040).

Almost surely, 2^2155508257 is an apocalyptic number.

It is an amenable number.

2155508257 is a deficient number, since it is larger than the sum of its proper divisors (548189663).

2155508257 is a wasteful number, since it uses less digits than its factorization.

2155508257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410 (or 391 counting only the distinct ones).

The product of its (nonzero) digits is 140000, while the sum is 40.

The square root of 2155508257 is about 46427.4515453950. The cubic root of 2155508257 is about 1291.7641582208.

The spelling of 2155508257 in words is "two billion, one hundred fifty-five million, five hundred eight thousand, two hundred fifty-seven".