31511151161 has 8 divisors (see below), whose sum is σ = 36026319360. Its totient is φ = 26999376768.

The previous prime is 31511151143. The next prime is 31511151187. The reversal of 31511151161 is 16115111513.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-31511151161 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31511151161.

It is not an unprimeable number, because it can be changed into a prime (31510151161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 828521 + ... + 865718.

It is an arithmetic number, because the mean of its divisors is an integer number (4503289920).

Almost surely, 2^31511151161 is an apocalyptic number.

It is an amenable number.

31511151161 is a deficient number, since it is larger than the sum of its proper divisors (4515168199).

31511151161 is a wasteful number, since it uses less digits than its factorization.

31511151161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1696903.

The product of its digits is 450, while the sum is 26.

Adding to 31511151161 its reverse (16115111513), we get a palindrome (47626262674).

The spelling of 31511151161 in words is "thirty-one billion, five hundred eleven million, one hundred fifty-one thousand, one hundred sixty-one".