31920718246389 has 24 divisors (see below), whose sum is σ = 52694710108352. Its totient is φ = 18240344277120.

The previous prime is 31920718246349. The next prime is 31920718246409. The reversal of 31920718246389 is 98364281702913.

31920718246389 is a `hidden beast` number, since 3 + 1 + 9 + 2 + 0 + 7 + 1 + 8 + 246 + 389 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-31920718246389 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31920718246349) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20536194 + ... + 22035804.

Almost surely, 2^{31920718246389} is an apocalyptic number.

It is an amenable number.

31920718246389 is a deficient number, since it is larger than the sum of its proper divisors (20773991861963).

31920718246389 is a wasteful number, since it uses less digits than its factorization.

31920718246389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1837497 (or 1837494 counting only the distinct ones).

The product of its (nonzero) digits is 31352832, while the sum is 63.

The spelling of 31920718246389 in words is "thirty-one trillion, nine hundred twenty billion, seven hundred eighteen million, two hundred forty-six thousand, three hundred eighty-nine".