315351521 has 4 divisors (see below), whose sum is σ = 315392532. Its totient is φ = 315310512.

The previous prime is 315351511. The next prime is 315351523. The reversal of 315351521 is 125153513.

It is a happy number.

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.

It can be written as a sum of positive squares in 2 ways, for example, as 79299025 + 236052496 = 8905^2 + 15364^2 .

It is a cyclic number.

It is not a de Polignac number, because 315351521 - 2¹⁸ = 315089377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (315351523) 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, 5126 + ... + 25631.

It is an arithmetic number, because the mean of its divisors is an integer number (78848133).

It is a Poulet number, since it divides 2^315351520-1.

Almost surely, 2^315351521 is an apocalyptic number.

315351521 is the 10253-rd octagonal number.

It is an amenable number.

315351521 is a deficient number, since it is larger than the sum of its proper divisors (41011).

315351521 is a wasteful number, since it uses less digits than its factorization.

315351521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41010.

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

The square root of 315351521 is about 17758.1395703491. The cubic root of 315351521 is about 680.6622160526.

The spelling of 315351521 in words is "three hundred fifteen million, three hundred fifty-one thousand, five hundred twenty-one".