20771607920 has 80 divisors (see below), whose sum is σ = 55233131520. Its totient is φ = 7116532992.

The previous prime is 20771607919. The next prime is 20771607931. The reversal of 20771607920 is 2970617702.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 804329 + ... + 829751.

It is an arithmetic number, because the mean of its divisors is an integer number (690414144).

Almost surely, 2^20771607920 is an apocalyptic number.

20771607920 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 20771607920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27616565760).

20771607920 is an abundant number, since it is smaller than the sum of its proper divisors (34461523600).

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

20771607920 is a wasteful number, since it uses less digits than its factorization.

20771607920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26902 (or 26896 counting only the distinct ones).

The product of its (nonzero) digits is 74088, while the sum is 41.

The spelling of 20771607920 in words is "twenty billion, seven hundred seventy-one million, six hundred seven thousand, nine hundred twenty".