20777357808 has 60 divisors (see below), whose sum is σ = 58299720960. Its totient is φ = 6907684608.

The previous prime is 20777357771. The next prime is 20777357849. The reversal of 20777357808 is 80875377702.

It is a happy number.

20777357808 is a `hidden beast` number, since 207 + 7 + 7 + 357 + 80 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 133213 + ... + 243516.

It is an arithmetic number, because the mean of its divisors is an integer number (971662016).

Almost surely, 2^20777357808 is an apocalyptic number.

It is an amenable number.

20777357808 is an abundant number, since it is smaller than the sum of its proper divisors (37522363152).

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

20777357808 is a wasteful number, since it uses less digits than its factorization.

20777357808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377126 (or 377117 counting only the distinct ones).

The product of its (nonzero) digits is 4609920, while the sum is 54.

The spelling of 20777357808 in words is "twenty billion, seven hundred seventy-seven million, three hundred fifty-seven thousand, eight hundred eight".