20605978800 has 1200 divisors, whose sum is σ = 90420105600. Its totient is φ = 4429209600.

The previous prime is 20605978759. The next prime is 20605978823. The reversal of 20605978800 is 887950602.

It is a tau number, because it is divible by the number of its divisors (1200).

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

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 115117111 + ... + 115117289.

It is an arithmetic number, because the mean of its divisors is an integer number (75350088).

Almost surely, 2^20605978800 is an apocalyptic number.

20605978800 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 20605978800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45210052800).

20605978800 is an abundant number, since it is smaller than the sum of its proper divisors (69814126800).

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

20605978800 is a wasteful number, since it uses less digits than its factorization.

20605978800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256 (or 236 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The spelling of 20605978800 in words is "twenty billion, six hundred five million, nine hundred seventy-eight thousand, eight hundred".