21213892224 has 576 divisors, whose sum is σ = 76186656000. Its totient is φ = 5852528640.

The previous prime is 21213892213. The next prime is 21213892253. The reversal of 21213892224 is 42229831212.

It is a happy number.

21213892224 is a `hidden beast` number, since 212 + 138 + 92 + 224 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

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, 47246752 + ... + 47247200.

It is an arithmetic number, because the mean of its divisors is an integer number (132268500).

Almost surely, 2^21213892224 is an apocalyptic number.

21213892224 is a gapful number since it is divisible by the number (24) 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 21213892224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38093328000).

21213892224 is an abundant number, since it is smaller than the sum of its proper divisors (54972763776).

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

21213892224 is an equidigital number, since it uses as much as digits as its factorization.

21213892224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 523 (or 492 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The spelling of 21213892224 in words is "twenty-one billion, two hundred thirteen million, eight hundred ninety-two thousand, two hundred twenty-four".