155117251 has 4 divisors (see below), whose sum is σ = 155516400. Its totient is φ = 154718104.

The previous prime is 155117243. The next prime is 155117269. The reversal of 155117251 is 152711551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 152711551 = 4759 ⋅32089.

It is a cyclic number.

It is not a de Polignac number, because 155117251 - 2³ = 155117243 is a prime.

It is a super-2 number, since 2×155117251² = 48122723115594002, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155117051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 198991 + ... + 199768.

It is an arithmetic number, because the mean of its divisors is an integer number (38879100).

Almost surely, 2^155117251 is an apocalyptic number.

155117251 is a deficient number, since it is larger than the sum of its proper divisors (399149).

155117251 is an equidigital number, since it uses as much as digits as its factorization.

155117251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399148.

The product of its digits is 1750, while the sum is 28.

The square root of 155117251 is about 12454.6076212782. The cubic root of 155117251 is about 537.3039498454.

The spelling of 155117251 in words is "one hundred fifty-five million, one hundred seventeen thousand, two hundred fifty-one".