20553321400 has 96 divisors (see below), whose sum is σ = 48892183200. Its totient is φ = 8033177600.

The previous prime is 20553321391. The next prime is 20553321407. The reversal of 20553321400 is 412335502.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20553321407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1598196 + ... + 1611004.

It is an arithmetic number, because the mean of its divisors is an integer number (509293575).

Almost surely, 2^20553321400 is an apocalyptic number.

20553321400 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 20553321400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24446091600).

20553321400 is an abundant number, since it is smaller than the sum of its proper divisors (28338861800).

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

20553321400 is a wasteful number, since it uses less digits than its factorization.

20553321400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13009 (or 13000 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 25.

Adding to 20553321400 its reverse (412335502), we get a palindrome (20965656902).

The spelling of 20553321400 in words is "twenty billion, five hundred fifty-three million, three hundred twenty-one thousand, four hundred".