21521422024 has 16 divisors (see below), whose sum is σ = 40360731120. Its totient is φ = 10758560400.

The previous prime is 21521421991. The next prime is 21521422057. The reversal of 21521422024 is 42022412512.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21521421991) and next prime (21521422057).

It is a super-2 number, since 2×21521422024² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21521422024.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 225894 + ... + 306709.

It is an arithmetic number, because the mean of its divisors is an integer number (2522545695).

Almost surely, 2^21521422024 is an apocalyptic number.

It is an amenable number.

21521422024 is a deficient number, since it is larger than the sum of its proper divisors (18839309096).

21521422024 is a wasteful number, since it uses less digits than its factorization.

21521422024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537660 (or 537656 counting only the distinct ones).

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

Adding to 21521422024 its reverse (42022412512), we get a palindrome (63543834536).

The spelling of 21521422024 in words is "twenty-one billion, five hundred twenty-one million, four hundred twenty-two thousand, twenty-four".