3921981724 has 12 divisors (see below), whose sum is σ = 6864789064. Its totient is φ = 1960613424.

The previous prime is 3921981683. The next prime is 3921981773. The reversal of 3921981724 is 4271891293.

It is a happy number.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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, 70299 + ... + 113074.

Almost surely, 2^3921981724 is an apocalyptic number.

It is an amenable number.

3921981724 is a deficient number, since it is larger than the sum of its proper divisors (2942807340).

3921981724 is a wasteful number, since it uses less digits than its factorization.

3921981724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188724 (or 188722 counting only the distinct ones).

The product of its digits is 217728, while the sum is 46.

The square root of 3921981724 is about 62625.7273331017. The cubic root of 3921981724 is about 1577.0126917225.

The spelling of 3921981724 in words is "three billion, nine hundred twenty-one million, nine hundred eighty-one thousand, seven hundred twenty-four".