20839820 has 12 divisors (see below), whose sum is σ = 43763664. Its totient is φ = 8335920.

The previous prime is 20839813. The next prime is 20839829. The reversal of 20839820 is 2893802.

It is a happy number.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (20839829) 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, 520976 + ... + 521015.

It is an arithmetic number, because the mean of its divisors is an integer number (3646972).

Almost surely, 2^20839820 is an apocalyptic number.

20839820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20839820 is an abundant number, since it is smaller than the sum of its proper divisors (22923844).

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

20839820 is a wasteful number, since it uses less digits than its factorization.

20839820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1042000 (or 1041998 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 20839820 is about 4565.0651693048. The cubic root of 20839820 is about 275.1891591130.

The spelling of 20839820 in words is "twenty million, eight hundred thirty-nine thousand, eight hundred twenty".