20639927 has 24 divisors (see below), whose sum is σ = 26470800. Its totient is φ = 15912960.

The previous prime is 20639923. The next prime is 20639939. The reversal of 20639927 is 72993602.

It is not a de Polignac number, because 20639927 - 2² = 20639923 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20639923) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80183 + ... + 80439.

It is an arithmetic number, because the mean of its divisors is an integer number (1102950).

Almost surely, 2^20639927 is an apocalyptic number.

20639927 is a deficient number, since it is larger than the sum of its proper divisors (5830873).

20639927 is a wasteful number, since it uses less digits than its factorization.

20639927 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431 (or 424 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 38.

The square root of 20639927 is about 4543.1186425186. The cubic root of 20639927 is about 274.3064706230.

The spelling of 20639927 in words is "twenty million, six hundred thirty-nine thousand, nine hundred twenty-seven".