31616536987 has 4 divisors (see below), whose sum is σ = 36133185136. Its totient is φ = 27099888840.

The previous prime is 31616536961. The next prime is 31616536993. The reversal of 31616536987 is 78963561613.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31616536987 - 2⁷ = 31616536859 is a prime.

It is a super-2 number, since 2×31616536987² (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 (31616536957) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2258324064 + ... + 2258324077.

It is an arithmetic number, because the mean of its divisors is an integer number (9033296284).

Almost surely, 2^31616536987 is an apocalyptic number.

31616536987 is a deficient number, since it is larger than the sum of its proper divisors (4516648149).

31616536987 is an equidigital number, since it uses as much as digits as its factorization.

31616536987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4516648148.

The product of its digits is 4898880, while the sum is 55.

The spelling of 31616536987 in words is "thirty-one billion, six hundred sixteen million, five hundred thirty-six thousand, nine hundred eighty-seven".