331305923679721 has 9 divisors (see below), whose sum is σ = 331524835738551. Its totient is φ = 331087156113312.

The previous prime is 331305923679667. The next prime is 331305923679743. The reversal of 331305923679721 is 127976329503133.

It is a happy number.

The square root of 331305923679721 is 18201811.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 167894085186025 + 163411838493696 = 12957395^2 + 12783264^2 .

It is not a de Polignac number, because 331305923679721 - 2³¹ = 331303776196073 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 331305923679721.

It is not an unprimeable number, because it can be changed into a prime (331305923679821) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 32344613026 + ... + 32344623268.

It is an arithmetic number, because the mean of its divisors is an integer number (36836092859839).

Almost surely, 2^{331305923679721} is an apocalyptic number.

331305923679721 is the 18201811-st square number.

331305923679721 is the 9100906-th centered octagonal number.

It is an amenable number.

331305923679721 is a deficient number, since it is larger than the sum of its proper divisors (218912058830).

331305923679721 is an frugal number, since it uses more digits than its factorization.

331305923679721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24040 (or 12020 counting only the distinct ones).

The product of its (nonzero) digits is 38578680, while the sum is 61.

The spelling of 331305923679721 in words is "three hundred thirty-one trillion, three hundred five billion, nine hundred twenty-three million, six hundred seventy-nine thousand, seven hundred twenty-one".