31988890358357 has 4 divisors (see below), whose sum is σ = 32222385908556. Its totient is φ = 31755394808160.

The previous prime is 31988890358329. The next prime is 31988890358407. The reversal of 31988890358357 is 75385309888913.

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 23998623547921 + 7990266810436 = 4898839^2 + 2826706^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31988890358357 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 (31988890358857) 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, 116747774894 + ... + 116747775167.

It is an arithmetic number, because the mean of its divisors is an integer number (8055596477139).

Almost surely, 2^{31988890358357} is an apocalyptic number.

It is an amenable number.

31988890358357 is a deficient number, since it is larger than the sum of its proper divisors (233495550199).

31988890358357 is a wasteful number, since it uses less digits than its factorization.

31988890358357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233495550198.

The product of its (nonzero) digits is 1567641600, while the sum is 77.

The spelling of 31988890358357 in words is "thirty-one trillion, nine hundred eighty-eight billion, eight hundred ninety million, three hundred fifty-eight thousand, three hundred fifty-seven".