21652234640 has 40 divisors (see below), whose sum is σ = 50355044928. Its totient is φ = 8658554240.

The previous prime is 21652234619. The next prime is 21652234691. The reversal of 21652234640 is 4643225612.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 21652234640.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 278279 + ... + 347481.

Almost surely, 2^21652234640 is an apocalyptic number.

21652234640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21652234640 is an abundant number, since it is smaller than the sum of its proper divisors (28702810288).

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

21652234640 is a wasteful number, since it uses less digits than its factorization.

21652234640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73127 (or 73121 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 35.

The spelling of 21652234640 in words is "twenty-one billion, six hundred fifty-two million, two hundred thirty-four thousand, six hundred forty".