155321513 has 4 divisors (see below), whose sum is σ = 156310980. Its totient is φ = 154332048.

The previous prime is 155321497. The next prime is 155321527. The reversal of 155321513 is 315123551.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 315123551 = 293 ⋅1075507.

It can be written as a sum of positive squares in 2 ways, for example, as 78092569 + 77228944 = 8837^2 + 8788^2 .

It is a cyclic number.

It is not a de Polignac number, because 155321513 - 2⁴ = 155321497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155321213) 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, 494498 + ... + 494811.

It is an arithmetic number, because the mean of its divisors is an integer number (39077745).

Almost surely, 2^155321513 is an apocalyptic number.

It is an amenable number.

155321513 is a deficient number, since it is larger than the sum of its proper divisors (989467).

155321513 is an equidigital number, since it uses as much as digits as its factorization.

155321513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 989466.

The product of its digits is 2250, while the sum is 26.

The square root of 155321513 is about 12462.8051818200. The cubic root of 155321513 is about 537.5396911739.

The spelling of 155321513 in words is "one hundred fifty-five million, three hundred twenty-one thousand, five hundred thirteen".