31861408787 has 8 divisors (see below), whose sum is σ = 34314715680. Its totient is φ = 29408448960.

The previous prime is 31861408781. The next prime is 31861408819. The reversal of 31861408787 is 78780416813.

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

It is a cyclic number.

It is not a de Polignac number, because 31861408787 - 2¹⁴ = 31861392403 is a prime.

It is a super-2 number, since 2×31861408787² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31861408781) 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, 122639 + ... + 280647.

It is an arithmetic number, because the mean of its divisors is an integer number (4289339460).

Almost surely, 2^31861408787 is an apocalyptic number.

31861408787 is a deficient number, since it is larger than the sum of its proper divisors (2453306893).

31861408787 is a wasteful number, since it uses less digits than its factorization.

31861408787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173533.

The product of its (nonzero) digits is 1806336, while the sum is 53.

The spelling of 31861408787 in words is "thirty-one billion, eight hundred sixty-one million, four hundred eight thousand, seven hundred eighty-seven".