31513451023 has 4 divisors (see below), whose sum is σ = 31525865320. Its totient is φ = 31501036728.

The previous prime is 31513451009. The next prime is 31513451093. The reversal of 31513451023 is 32015431513.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31513451023 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31513450982 and 31513451000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31513451093) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6203340 + ... + 6208417.

It is an arithmetic number, because the mean of its divisors is an integer number (7881466330).

Almost surely, 2^31513451023 is an apocalyptic number.

31513451023 is a deficient number, since it is larger than the sum of its proper divisors (12414297).

31513451023 is a wasteful number, since it uses less digits than its factorization.

31513451023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12414296.

The product of its (nonzero) digits is 5400, while the sum is 28.

Adding to 31513451023 its reverse (32015431513), we get a palindrome (63528882536).

The spelling of 31513451023 in words is "thirty-one billion, five hundred thirteen million, four hundred fifty-one thousand, twenty-three".