155661051 has 32 divisors (see below), whose sum is σ = 261692928. Its totient is φ = 80098560.

The previous prime is 155661043. The next prime is 155661097. The reversal of 155661051 is 150166551.

It is not a de Polignac number, because 155661051 - 2³ = 155661043 is a prime.

It is not an unprimeable number, because it can be changed into a prime (155661001) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4240 + ... + 18146.

It is an arithmetic number, because the mean of its divisors is an integer number (8177904).

Almost surely, 2^155661051 is an apocalyptic number.

155661051 is a deficient number, since it is larger than the sum of its proper divisors (106031877).

155661051 is a wasteful number, since it uses less digits than its factorization.

155661051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13971.

The product of its (nonzero) digits is 4500, while the sum is 30.

The square root of 155661051 is about 12476.4197989648. The cubic root of 155661051 is about 537.9310993240.

Subtracting from 155661051 its product of nonzero digits (4500), we obtain a palindrome (155656551).

The spelling of 155661051 in words is "one hundred fifty-five million, six hundred sixty-one thousand, fifty-one".