31687140387 has 32 divisors (see below), whose sum is σ = 48576005632. Its totient is φ = 17998205184.

The previous prime is 31687140301. The next prime is 31687140391. The reversal of 31687140387 is 78304178613.

It is not a de Polignac number, because 31687140387 - 2¹² = 31687136291 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31687140487) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2398143 + ... + 2411319.

It is an arithmetic number, because the mean of its divisors is an integer number (1518000176).

Almost surely, 2^31687140387 is an apocalyptic number.

31687140387 is a deficient number, since it is larger than the sum of its proper divisors (16888865245).

31687140387 is a wasteful number, since it uses less digits than its factorization.

31687140387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13867.

The product of its (nonzero) digits is 677376, while the sum is 48.

The spelling of 31687140387 in words is "thirty-one billion, six hundred eighty-seven million, one hundred forty thousand, three hundred eighty-seven".