21122573400 has 288 divisors, whose sum is σ = 73838466000. Its totient is φ = 5404707840.

The previous prime is 21122573377. The next prime is 21122573419. The reversal of 21122573400 is 437522112.

21122573400 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 257 + 3 + 400 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 9029431 + ... + 9031769.

Almost surely, 2^21122573400 is an apocalyptic number.

21122573400 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 21122573400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36919233000).

21122573400 is an abundant number, since it is smaller than the sum of its proper divisors (52715892600).

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

21122573400 is a wasteful number, since it uses less digits than its factorization.

21122573400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2563 (or 2551 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The spelling of 21122573400 in words is "twenty-one billion, one hundred twenty-two million, five hundred seventy-three thousand, four hundred".