21839695920 has 720 divisors, whose sum is σ = 92795489280. Its totient is φ = 4572288000.

The previous prime is 21839695909. The next prime is 21839695957. The reversal of 21839695920 is 2959693812.

It is a happy number.

21839695920 is a `hidden beast` number, since 2 + 18 + 39 + 6 + 9 + 592 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 20779395 + ... + 20780445.

It is an arithmetic number, because the mean of its divisors is an integer number (128882624).

Almost surely, 2^21839695920 is an apocalyptic number.

21839695920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21839695920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46397744640).

21839695920 is an abundant number, since it is smaller than the sum of its proper divisors (70955793360).

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

21839695920 is a wasteful number, since it uses less digits than its factorization.

21839695920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1134 (or 1118 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The spelling of 21839695920 in words is "twenty-one billion, eight hundred thirty-nine million, six hundred ninety-five thousand, nine hundred twenty".