31607720551 has 12 divisors (see below), whose sum is σ = 34943216616. Its totient is φ = 28568178320.

The previous prime is 31607720527. The next prime is 31607720563. The reversal of 31607720551 is 15502770613.

It is a de Polignac number, because none of the positive numbers 2^k-31607720551 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31607720551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31607730551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 734041 + ... + 775906.

It is an arithmetic number, because the mean of its divisors is an integer number (2911934718).

Almost surely, 2^31607720551 is an apocalyptic number.

31607720551 is a deficient number, since it is larger than the sum of its proper divisors (3335496065).

31607720551 is a wasteful number, since it uses less digits than its factorization.

31607720551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1510142 (or 1510131 counting only the distinct ones).

The product of its (nonzero) digits is 44100, while the sum is 37.

The spelling of 31607720551 in words is "thirty-one billion, six hundred seven million, seven hundred twenty thousand, five hundred fifty-one".