315299821 has 4 divisors (see below), whose sum is σ = 315442144. Its totient is φ = 315157500.

The previous prime is 315299797. The next prime is 315299843. The reversal of 315299821 is 128992513.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 315299821 - 2¹⁵ = 315267053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (315299891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67785 + ... + 72286.

It is an arithmetic number, because the mean of its divisors is an integer number (78860536).

Almost surely, 2^315299821 is an apocalyptic number.

It is an amenable number.

315299821 is a deficient number, since it is larger than the sum of its proper divisors (142323).

315299821 is a wasteful number, since it uses less digits than its factorization.

315299821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142322.

The product of its digits is 38880, while the sum is 40.

The square root of 315299821 is about 17756.6838401769. The cubic root of 315299821 is about 680.6250171836.

The spelling of 315299821 in words is "three hundred fifteen million, two hundred ninety-nine thousand, eight hundred twenty-one".