31589711987 has 2 divisors, whose sum is σ = 31589711988. Its totient is φ = 31589711986.

The previous prime is 31589711983. The next prime is 31589712019. The reversal of 31589711987 is 78911798513.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31589711987 - 2² = 31589711983 is a prime.

It is a super-2 number, since 2×31589711987² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31589711983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15794855993 + 15794855994.

It is an arithmetic number, because the mean of its divisors is an integer number (15794855994).

Almost surely, 2^31589711987 is an apocalyptic number.

31589711987 is a deficient number, since it is larger than the sum of its proper divisors (1).

31589711987 is an equidigital number, since it uses as much as digits as its factorization.

31589711987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3810240, while the sum is 59.

The spelling of 31589711987 in words is "thirty-one billion, five hundred eighty-nine million, seven hundred eleven thousand, nine hundred eighty-seven".