20639142 has 24 divisors (see below), whose sum is σ = 46663344. Its totient is φ = 6580464.

The previous prime is 20639141. The next prime is 20639147. The reversal of 20639142 is 24193602.

20639142 is a `hidden beast` number, since 20 + 639 + 1 + 4 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20639141) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24513 + ... + 25340.

It is an arithmetic number, because the mean of its divisors is an integer number (1944306).

Almost surely, 2^20639142 is an apocalyptic number.

20639142 is an abundant number, since it is smaller than the sum of its proper divisors (26024202).

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

20639142 is a wasteful number, since it uses less digits than its factorization.

20639142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49884 (or 49881 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 20639142 is about 4543.0322472992. The cubic root of 20639142 is about 274.3029930056.

The spelling of 20639142 in words is "twenty million, six hundred thirty-nine thousand, one hundred forty-two".