20605777920 has 1296 divisors, whose sum is σ = 93289439880. Its totient is φ = 4347592704.

The previous prime is 20605777919. The next prime is 20605777931. The reversal of 20605777920 is 2977750602.

20605777920 is a `hidden beast` number, since 2 + 0 + 6 + 0 + 577 + 79 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1296).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 1585059834 + ... + 1585059846.

Almost surely, 2^20605777920 is an apocalyptic number.

20605777920 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 20605777920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46644719940).

20605777920 is an abundant number, since it is smaller than the sum of its proper divisors (72683661960).

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

20605777920 is an equidigital number, since it uses as much as digits as its factorization.

20605777920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 370440, while the sum is 45.

The spelling of 20605777920 in words is "twenty billion, six hundred five million, seven hundred seventy-seven thousand, nine hundred twenty".