2315202721 has 4 divisors (see below), whose sum is σ = 2493295252. Its totient is φ = 2137110192.

The previous prime is 2315202713. The next prime is 2315202727. The reversal of 2315202721 is 1272025132.

2315202721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1453134400 + 862068321 = 38120^2 + 29361^2 .

It is a cyclic number.

It is not a de Polignac number, because 2315202721 - 2³ = 2315202713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2315202727) 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, 89046246 + ... + 89046271.

It is an arithmetic number, because the mean of its divisors is an integer number (623323813).

Almost surely, 2^2315202721 is an apocalyptic number.

It is an amenable number.

2315202721 is a deficient number, since it is larger than the sum of its proper divisors (178092531).

2315202721 is a wasteful number, since it uses less digits than its factorization.

2315202721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178092530.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 2315202721 is about 48116.5535029266. The cubic root of 2315202721 is about 1322.9080973688.

Adding to 2315202721 its reverse (1272025132), we get a palindrome (3587227853).

The spelling of 2315202721 in words is "two billion, three hundred fifteen million, two hundred two thousand, seven hundred twenty-one".