31781398472 has 16 divisors (see below), whose sum is σ = 59752498560. Its totient is φ = 15847398864.

The previous prime is 31781398469. The next prime is 31781398483. The reversal of 31781398472 is 27489318713.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5409428 + ... + 5415299.

It is an arithmetic number, because the mean of its divisors is an integer number (3734531160).

Almost surely, 2^31781398472 is an apocalyptic number.

It is an amenable number.

31781398472 is a deficient number, since it is larger than the sum of its proper divisors (27971100088).

31781398472 is a wasteful number, since it uses less digits than its factorization.

31781398472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10825100 (or 10825096 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 53.

The spelling of 31781398472 in words is "thirty-one billion, seven hundred eighty-one million, three hundred ninety-eight thousand, four hundred seventy-two".