31161121501 has 16 divisors (see below), whose sum is σ = 32190572160. Its totient is φ = 30141927360.

The previous prime is 31161121463. The next prime is 31161121507. The reversal of 31161121501 is 10512116113.

It is a cyclic number.

It is not a de Polignac number, because 31161121501 - 2⁷ = 31161121373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31161121507) 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, 6893320 + ... + 6897838.

It is an arithmetic number, because the mean of its divisors is an integer number (2011910760).

Almost surely, 2^31161121501 is an apocalyptic number.

It is an amenable number.

31161121501 is a deficient number, since it is larger than the sum of its proper divisors (1029450659).

31161121501 is a wasteful number, since it uses less digits than its factorization.

31161121501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5604.

The product of its (nonzero) digits is 180, while the sum is 22.

Adding to 31161121501 its reverse (10512116113), we get a palindrome (41673237614).

The spelling of 31161121501 in words is "thirty-one billion, one hundred sixty-one million, one hundred twenty-one thousand, five hundred one".