31311020511 has 6 divisors (see below), whose sum is σ = 45227029640. Its totient is φ = 20874013668.

The previous prime is 31311020509. The next prime is 31311020557. The reversal of 31311020511 is 11502011313.

31311020511 is a `hidden beast` number, since 3 + 131 + 1 + 0 + 20 + 511 = 666.

It is not a de Polignac number, because 31311020511 - 2¹ = 31311020509 is a prime.

It is a super-2 number, since 2×31311020511² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31311020011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1739501131 + ... + 1739501148.

Almost surely, 2^31311020511 is an apocalyptic number.

31311020511 is a deficient number, since it is larger than the sum of its proper divisors (13916009129).

31311020511 is a wasteful number, since it uses less digits than its factorization.

31311020511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3479002285 (or 3479002282 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 18.

Adding to 31311020511 its reverse (11502011313), we get a palindrome (42813031824).

The spelling of 31311020511 in words is "thirty-one billion, three hundred eleven million, twenty thousand, five hundred eleven".