31812646321 has 3 divisors (see below), whose sum is σ = 31812824683. Its totient is φ = 31812467960.

The previous prime is 31812646291. The next prime is 31812646357. The reversal of 31812646321 is 12364621813.

The square root of 31812646321 is 178361.

It is a perfect power (a square), and thus also a powerful 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 only one way, i.e., 3400172721 + 28412473600 = 58311^2 + 168560^2 .

It is not a de Polignac number, because 31812646321 - 2¹³ = 31812638129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31812646721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 89181 + ... + 267541.

Almost surely, 2^31812646321 is an apocalyptic number.

31812646321 is the 178361-st square number.

31812646321 is the 89181-st centered octagonal number.

It is an amenable number.

31812646321 is a deficient number, since it is larger than the sum of its proper divisors (178362).

31812646321 is an frugal number, since it uses more digits than its factorization.

31812646321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356722 (or 178361 counting only the distinct ones).

The product of its digits is 41472, while the sum is 37.

The spelling of 31812646321 in words is "thirty-one billion, eight hundred twelve million, six hundred forty-six thousand, three hundred twenty-one".