20139744 has 24 divisors (see below), whose sum is σ = 52867080. Its totient is φ = 6713216.

The previous prime is 20139737. The next prime is 20139773. The reversal of 20139744 is 44793102.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (24).

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, 104799 + ... + 104990.

It is an arithmetic number, because the mean of its divisors is an integer number (2202795).

Almost surely, 2^20139744 is an apocalyptic number.

20139744 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20139744 is an abundant number, since it is smaller than the sum of its proper divisors (32727336).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20139744 is a wasteful number, since it uses less digits than its factorization.

20139744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209802 (or 209794 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 20139744 is about 4487.7326123556. The cubic root of 20139744 is about 272.0725008579.

The spelling of 20139744 in words is "twenty million, one hundred thirty-nine thousand, seven hundred forty-four".