31181949091 has 16 divisors (see below), whose sum is σ = 32866848000. Its totient is φ = 29525731488.

The previous prime is 31181949077. The next prime is 31181949103. The reversal of 31181949091 is 19094918113.

It is not a de Polignac number, because 31181949091 - 2¹⁵ = 31181916323 is a prime.

It is a super-2 number, since 2×31181949091² (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 (31181949011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1101780 + ... + 1129726.

It is an arithmetic number, because the mean of its divisors is an integer number (2054178000).

Almost surely, 2^31181949091 is an apocalyptic number.

31181949091 is a deficient number, since it is larger than the sum of its proper divisors (1684898909).

31181949091 is a wasteful number, since it uses less digits than its factorization.

31181949091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28458.

The product of its (nonzero) digits is 69984, while the sum is 46.

The spelling of 31181949091 in words is "thirty-one billion, one hundred eighty-one million, nine hundred forty-nine thousand, ninety-one".