21221322452 has 96 divisors (see below), whose sum is σ = 43998850560. Its totient is φ = 8852976000.

The previous prime is 21221322449. The next prime is 21221322481. The reversal of 21221322452 is 25422312212.

It is a super-2 number, since 2×21221322452² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3413627 + ... + 3419837.

It is an arithmetic number, because the mean of its divisors is an integer number (458321360).

Almost surely, 2^21221322452 is an apocalyptic number.

21221322452 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21221322452 is an abundant number, since it is smaller than the sum of its proper divisors (22777528108).

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

21221322452 is a wasteful number, since it uses less digits than its factorization.

21221322452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6373 (or 6371 counting only the distinct ones).

The product of its digits is 3840, while the sum is 26.

Adding to 21221322452 its reverse (25422312212), we get a palindrome (46643634664).

The spelling of 21221322452 in words is "twenty-one billion, two hundred twenty-one million, three hundred twenty-two thousand, four hundred fifty-two".