21652621624 has 8 divisors (see below), whose sum is σ = 40598665560. Its totient is φ = 10826310808.

The previous prime is 21652621609. The next prime is 21652621631. The reversal of 21652621624 is 42612625612.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21652621624² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1353288844 + ... + 1353288859.

It is an arithmetic number, because the mean of its divisors is an integer number (5074833195).

Almost surely, 2^21652621624 is an apocalyptic number.

It is an amenable number.

21652621624 is a deficient number, since it is larger than the sum of its proper divisors (18946043936).

21652621624 is a wasteful number, since it uses less digits than its factorization.

21652621624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2706577709 (or 2706577705 counting only the distinct ones).

The product of its digits is 69120, while the sum is 37.

The spelling of 21652621624 in words is "twenty-one billion, six hundred fifty-two million, six hundred twenty-one thousand, six hundred twenty-four".