20553530400 has 432 divisors, whose sum is σ = 82649725704. Its totient is φ = 4761354240.

The previous prime is 20553530363. The next prime is 20553530407. The reversal of 20553530400 is 403535502.

20553530400 is a `hidden beast` number, since 20 + 553 + 53 + 0 + 40 + 0 = 666.

It can be written as a sum of positive squares in 12 ways, for example, as 1039675536 + 19513854864 = 32244^2 + 139692^2 .

It is a super-2 number, since 2×20553530400² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20553530407) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1584742 + ... + 1597658.

Almost surely, 2^20553530400 is an apocalyptic number.

20553530400 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 20553530400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41324862852).

20553530400 is an abundant number, since it is smaller than the sum of its proper divisors (62096195304).

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

20553530400 is a wasteful number, since it uses less digits than its factorization.

20553530400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12973 (or 12957 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 27.

The spelling of 20553530400 in words is "twenty billion, five hundred fifty-three million, five hundred thirty thousand, four hundred".