21988675464 has 64 divisors (see below), whose sum is σ = 65556311040. Its totient is φ = 6009326400.

The previous prime is 21988675459. The next prime is 21988675591. The reversal of 21988675464 is 46457688912.

It is a happy number.

It is a super-2 number, since 2×21988675464² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21988675398 and 21988675407.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2841462 + ... + 2849189.

It is an arithmetic number, because the mean of its divisors is an integer number (1024317360).

Almost surely, 2^21988675464 is an apocalyptic number.

21988675464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21988675464 is an abundant number, since it is smaller than the sum of its proper divisors (43567635576).

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

21988675464 is a wasteful number, since it uses less digits than its factorization.

21988675464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5690690 (or 5690686 counting only the distinct ones).

The product of its digits is 23224320, while the sum is 60.

The spelling of 21988675464 in words is "twenty-one billion, nine hundred eighty-eight million, six hundred seventy-five thousand, four hundred sixty-four".