31397921101440 has 128 divisors (see below), whose sum is σ = 111200970628800. Its totient is φ = 8372778955776.

The previous prime is 31397921101433. The next prime is 31397921101471. The reversal of 31397921101440 is 4410112979313.

31397921101440 is a `hidden beast` number, since 3 + 1 + 3 + 9 + 7 + 92 + 110 + 1 + 440 = 666.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 908487382 + ... + 908521941.

Almost surely, 2^{31397921101440} is an apocalyptic number.

31397921101440 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31397921101440 is an abundant number, since it is smaller than the sum of its proper divisors (79803049527360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31397921101440 is a wasteful number, since it uses less digits than its factorization.

31397921101440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1817009351 (or 1817009333 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The spelling of 31397921101440 in words is "thirty-one trillion, three hundred ninety-seven billion, nine hundred twenty-one million, one hundred one thousand, four hundred forty".