155972513 has 4 divisors (see below), whose sum is σ = 155997828. Its totient is φ = 155947200.

The previous prime is 155972497. The next prime is 155972519. The reversal of 155972513 is 315279551.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 315279551 = 2347 ⋅134333.

It can be written as a sum of positive squares in 2 ways, for example, as 124925329 + 31047184 = 11177^2 + 5572^2 .

It is a cyclic number.

It is not a de Polignac number, because 155972513 - 2⁴ = 155972497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155972519) 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, 3245 + ... + 17957.

It is an arithmetic number, because the mean of its divisors is an integer number (38999457).

Almost surely, 2^155972513 is an apocalyptic number.

It is an amenable number.

155972513 is a deficient number, since it is larger than the sum of its proper divisors (25315).

155972513 is a wasteful number, since it uses less digits than its factorization.

155972513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25314.

The product of its digits is 47250, while the sum is 38.

The square root of 155972513 is about 12488.8955876811. The cubic root of 155972513 is about 538.2896421796.

The spelling of 155972513 in words is "one hundred fifty-five million, nine hundred seventy-two thousand, five hundred thirteen".