21252153400 has 96 divisors (see below), whose sum is σ = 50148576000. Its totient is φ = 8374504320.

The previous prime is 21252153361. The next prime is 21252153437. The reversal of 21252153400 is 435125212.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8641371 + ... + 8643829.

It is an arithmetic number, because the mean of its divisors is an integer number (522381000).

Almost surely, 2^21252153400 is an apocalyptic number.

21252153400 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 21252153400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25074288000).

21252153400 is an abundant number, since it is smaller than the sum of its proper divisors (28896422600).

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

21252153400 is a wasteful number, since it uses less digits than its factorization.

21252153400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3101 (or 3092 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

Adding to 21252153400 its reverse (435125212), we get a palindrome (21687278612).

The spelling of 21252153400 in words is "twenty-one billion, two hundred fifty-two million, one hundred fifty-three thousand, four hundred".