19979924 has 6 divisors (see below), whose sum is σ = 34964874. Its totient is φ = 9989960.

The previous prime is 19979923. The next prime is 19979929. The reversal of 19979924 is 42997991.

It can be written as a sum of positive squares in only one way, i.e., 19963024 + 16900 = 4468^2 + 130^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19979923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2497487 + ... + 2497494.

It is an arithmetic number, because the mean of its divisors is an integer number (5827479).

Almost surely, 2^19979924 is an apocalyptic number.

It is an amenable number.

19979924 is a deficient number, since it is larger than the sum of its proper divisors (14984950).

19979924 is a wasteful number, since it uses less digits than its factorization.

19979924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4994985 (or 4994983 counting only the distinct ones).

The product of its digits is 367416, while the sum is 50.

The square root of 19979924 is about 4469.8908264073. The cubic root of 19979924 is about 271.3509068392.

The spelling of 19979924 in words is "nineteen million, nine hundred seventy-nine thousand, nine hundred twenty-four".