155172997 has 8 divisors (see below), whose sum is σ = 183456000. Its totient is φ = 128418864.

The previous prime is 155172947. The next prime is 155173001. The reversal of 155172997 is 799271551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 155172997 - 2¹⁵ = 155140229 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155172947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 381997 + ... + 382402.

It is an arithmetic number, because the mean of its divisors is an integer number (22932000).

Almost surely, 2^155172997 is an apocalyptic number.

It is an amenable number.

155172997 is a deficient number, since it is larger than the sum of its proper divisors (28283003).

155172997 is an equidigital number, since it uses as much as digits as its factorization.

155172997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 764435.

The product of its digits is 198450, while the sum is 46.

The square root of 155172997 is about 12456.8453871757. The cubic root of 155172997 is about 537.3683075240.

The spelling of 155172997 in words is "one hundred fifty-five million, one hundred seventy-two thousand, nine hundred ninety-seven".