20379904 has 18 divisors (see below), whose sum is σ = 40680710. Its totient is φ = 10189824.

The previous prime is 20379899. The next prime is 20379907. The reversal of 20379904 is 40997302.

It can be written as a sum of positive squares in only one way, i.e., 18939904 + 1440000 = 4352^2 + 1200^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20379904.

It is not an unprimeable number, because it can be changed into a prime (20379907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39549 + ... + 40060.

Almost surely, 2^20379904 is an apocalyptic number.

It is an amenable number.

20379904 is a deficient number, since it is larger than the sum of its proper divisors (20300806).

20379904 is an frugal number, since it uses more digits than its factorization.

20379904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79625 (or 79611 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 20379904 is about 4514.4107035138. The cubic root of 20379904 is about 273.1496895854.

The spelling of 20379904 in words is "twenty million, three hundred seventy-nine thousand, nine hundred four".