20813221884 has 96 divisors (see below), whose sum is σ = 59799430656. Its totient is φ = 5486618880.

The previous prime is 20813221883. The next prime is 20813221969. The reversal of 20813221884 is 48812231802.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20813221883) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3776659 + ... + 3782165.

It is an arithmetic number, because the mean of its divisors is an integer number (622910736).

Almost surely, 2^20813221884 is an apocalyptic number.

It is an amenable number.

20813221884 is an abundant number, since it is smaller than the sum of its proper divisors (38986208772).

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

20813221884 is a wasteful number, since it uses less digits than its factorization.

20813221884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8995 (or 8993 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 39.

The spelling of 20813221884 in words is "twenty billion, eight hundred thirteen million, two hundred twenty-one thousand, eight hundred eighty-four".