20857913584 has 40 divisors (see below), whose sum is σ = 42284436480. Its totient is φ = 9948278208.

The previous prime is 20857913509. The next prime is 20857913597. The reversal of 20857913584 is 48531975802.

It is a happy number.

It is a super-2 number, since 2×20857913584² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57837 + ... + 212275.

It is an arithmetic number, because the mean of its divisors is an integer number (1057110912).

Almost surely, 2^20857913584 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20857913584, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21142218240).

20857913584 is an abundant number, since it is smaller than the sum of its proper divisors (21426522896).

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

20857913584 is a wasteful number, since it uses less digits than its factorization.

20857913584 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154837 (or 154831 counting only the distinct ones).

The product of its (nonzero) digits is 2419200, while the sum is 52.

The spelling of 20857913584 in words is "twenty billion, eight hundred fifty-seven million, nine hundred thirteen thousand, five hundred eighty-four".