20857873824 has 36 divisors (see below), whose sum is σ = 59314579506. Its totient is φ = 6952624512.

The previous prime is 20857873823. The next prime is 20857873831. The reversal of 20857873824 is 42837875802.

20857873824 is a `hidden beast` number, since 208 + 57 + 8 + 7 + 382 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19326560400 + 1531313424 = 139020^2 + 39132^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (20857873823) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36211299 + ... + 36211874.

Almost surely, 2^20857873824 is an apocalyptic number.

20857873824 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20857873824 is an abundant number, since it is smaller than the sum of its proper divisors (38456705682).

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

20857873824 is a wasteful number, since it uses less digits than its factorization.

20857873824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72423189 (or 72423178 counting only the distinct ones).

The product of its (nonzero) digits is 6021120, while the sum is 54.

The spelling of 20857873824 in words is "twenty billion, eight hundred fifty-seven million, eight hundred seventy-three thousand, eight hundred twenty-four".