31801953157 has 4 divisors (see below), whose sum is σ = 34248257260. Its totient is φ = 29355649056.

The previous prime is 31801953149. The next prime is 31801953163. The reversal of 31801953157 is 75135910813.

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

It can be written as a sum of positive squares in 2 ways, for example, as 19720865761 + 12081087396 = 140431^2 + 109914^2 .

It is a cyclic number.

It is not a de Polignac number, because 31801953157 - 2³ = 31801953149 is a prime.

It is a super-2 number, since 2×31801953157² (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 (31801953107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1223152032 + ... + 1223152057.

It is an arithmetic number, because the mean of its divisors is an integer number (8562064315).

Almost surely, 2^31801953157 is an apocalyptic number.

It is an amenable number.

31801953157 is a deficient number, since it is larger than the sum of its proper divisors (2446304103).

31801953157 is a wasteful number, since it uses less digits than its factorization.

31801953157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2446304102.

The product of its (nonzero) digits is 113400, while the sum is 43.

The spelling of 31801953157 in words is "thirty-one billion, eight hundred one million, nine hundred fifty-three thousand, one hundred fifty-seven".