155165553 has 6 divisors (see below), whose sum is σ = 224128034. Its totient is φ = 103443696.

The previous prime is 155165551. The next prime is 155165557. The reversal of 155165553 is 355561551.

155165553 is a `hidden beast` number, since 1 + 551 + 6 + 55 + 53 = 666.

It can be written as a sum of positive squares in only one way, i.e., 128663649 + 26501904 = 11343^2 + 5148^2 .

It is not a de Polignac number, because 155165553 - 2¹ = 155165551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155165551) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8620300 + ... + 8620317.

Almost surely, 2^155165553 is an apocalyptic number.

It is an amenable number.

155165553 is a deficient number, since it is larger than the sum of its proper divisors (68962481).

155165553 is a wasteful number, since it uses less digits than its factorization.

155165553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17240623 (or 17240620 counting only the distinct ones).

The product of its digits is 56250, while the sum is 36.

The square root of 155165553 is about 12456.5465920535. The cubic root of 155165553 is about 537.3597144618.

The spelling of 155165553 in words is "one hundred fifty-five million, one hundred sixty-five thousand, five hundred fifty-three".