31661931844 has 9 divisors (see below), whose sum is σ = 55409003517. Its totient is φ = 15830787984.

The previous prime is 31661931841. The next prime is 31661931853. The reversal of 31661931844 is 44813916613.

The square root of 31661931844 is 177938.

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., 21597829444 + 10064102400 = 146962^2 + 100320^2 .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31661931794 and 31661931803.

It is not an unprimeable number, because it can be changed into a prime (31661931841) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 311392 + ... + 400360.

Almost surely, 2^31661931844 is an apocalyptic number.

31661931844 is the 177938-th square number.

It is an amenable number.

31661931844 is a deficient number, since it is larger than the sum of its proper divisors (23747071673).

31661931844 is an frugal number, since it uses more digits than its factorization.

31661931844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177942 (or 88971 counting only the distinct ones).

The product of its digits is 373248, while the sum is 46.

The spelling of 31661931844 in words is "thirty-one billion, six hundred sixty-one million, nine hundred thirty-one thousand, eight hundred forty-four".