20639344 has 20 divisors (see below), whose sum is σ = 43624440. Its totient is φ = 9381440.

The previous prime is 20639341. The next prime is 20639347. The reversal of 20639344 is 44393602.

It is an interprime number because it is at equal distance from previous prime (20639341) and next prime (20639347).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20639341) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58459 + ... + 58810.

It is an arithmetic number, because the mean of its divisors is an integer number (2181222).

Almost surely, 2^20639344 is an apocalyptic number.

It is an amenable number.

20639344 is an abundant number, since it is smaller than the sum of its proper divisors (22985096).

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

20639344 is a wasteful number, since it uses less digits than its factorization.

20639344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117288 (or 117282 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 31.

The square root of 20639344 is about 4543.0544790922. The cubic root of 20639344 is about 274.3038878914.

The spelling of 20639344 in words is "twenty million, six hundred thirty-nine thousand, three hundred forty-four".