31639467420 has 144 divisors (see below), whose sum is σ = 105010764768. Its totient is φ = 7647252480.

The previous prime is 31639467403. The next prime is 31639467439. The reversal of 31639467420 is 2476493613.

31639467420 is a `hidden beast` number, since 3 + 1 + 639 + 4 + 6 + 7 + 4 + 2 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 643552 + ... + 690968.

It is an arithmetic number, because the mean of its divisors is an integer number (729241422).

Almost surely, 2^31639467420 is an apocalyptic number.

31639467420 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31639467420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52505382384).

31639467420 is an abundant number, since it is smaller than the sum of its proper divisors (73371297348).

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

31639467420 is a wasteful number, since it uses less digits than its factorization.

31639467420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47780 (or 47775 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 45.

The spelling of 31639467420 in words is "thirty-one billion, six hundred thirty-nine million, four hundred sixty-seven thousand, four hundred twenty".