20439988 has 12 divisors (see below), whose sum is σ = 35929152. Its totient is φ = 10174520.

The previous prime is 20439959. The next prime is 20440039. The reversal of 20439988 is 88993402.

It is a happy number.

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, 10348 + ... + 12163.

It is an arithmetic number, because the mean of its divisors is an integer number (2994096).

Almost surely, 2^20439988 is an apocalyptic number.

It is an amenable number.

20439988 is a deficient number, since it is larger than the sum of its proper divisors (15489164).

20439988 is a wasteful number, since it uses less digits than its factorization.

20439988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22742 (or 22740 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 43.

The square root of 20439988 is about 4521.0604950609. The cubic root of 20439988 is about 273.4178593762.

The spelling of 20439988 in words is "twenty million, four hundred thirty-nine thousand, nine hundred eighty-eight".