21054424020100 has 81 divisors (see below), whose sum is σ = 46063430968527. Its totient is φ = 8353143852480.

The previous prime is 21054424020067. The next prime is 21054424020109. The reversal of 21054424020100 is 102042445012.

The square root of 21054424020100 is 4588510.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 12996183620484 + 8058240399616 = 3605022^2 + 2838704^2 .

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21054424020109) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 5827405894 + ... + 5827409506.

Almost surely, 2^{21054424020100} is an apocalyptic number.

21054424020100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21054424020100 is the 4588510-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21054424020100

21054424020100 is an abundant number, since it is smaller than the sum of its proper divisors (25009006948427).

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

21054424020100 is an frugal number, since it uses more digits than its factorization.

21054424020100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7494 (or 3747 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 25.

Multiplying 21054424020100 by its sum of digits (25), we get a square (526360600502500 = 22942550²).

21054424020100 divided by its sum of digits (25) gives a square (842176960804 = 917702²).

Adding to 21054424020100 its reverse (102042445012), we get a palindrome (21156466465112).

The spelling of 21054424020100 in words is "twenty-one trillion, fifty-four billion, four hundred twenty-four million, twenty thousand, one hundred".