3972391918 has 32 divisors (see below), whose sum is σ = 6650703360. Its totient is φ = 1764322560.

The previous prime is 3972391909. The next prime is 3972391933. The reversal of 3972391918 is 8191932793.

It is a congruent number.

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, 156805 + ... + 180367.

It is an arithmetic number, because the mean of its divisors is an integer number (207834480).

Almost surely, 2^3972391918 is an apocalyptic number.

3972391918 is a deficient number, since it is larger than the sum of its proper divisors (2678311442).

3972391918 is a wasteful number, since it uses less digits than its factorization.

3972391918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23752.

The product of its digits is 734832, while the sum is 52.

The square root of 3972391918 is about 63026.9142351107. The cubic root of 3972391918 is about 1583.7405257967.

The spelling of 3972391918 in words is "three billion, nine hundred seventy-two million, three hundred ninety-one thousand, nine hundred eighteen".