31861379 has 8 divisors (see below), whose sum is σ = 35033088. Its totient is φ = 28735560.

The previous prime is 31861369. The next prime is 31861391. The reversal of 31861379 is 97316813.

31861379 = 220² + 221² + ... + 473².

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31861379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31861339) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10007 + ... + 12800.

It is an arithmetic number, because the mean of its divisors is an integer number (4379136).

Almost surely, 2^31861379 is an apocalyptic number.

31861379 is a deficient number, since it is larger than the sum of its proper divisors (3171709).

31861379 is a wasteful number, since it uses less digits than its factorization.

31861379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22945.

The product of its digits is 27216, while the sum is 38.

The square root of 31861379 is about 5644.5884703847. The cubic root of 31861379 is about 317.0211153326.

The spelling of 31861379 in words is "thirty-one million, eight hundred sixty-one thousand, three hundred seventy-nine".