21642620516 has 12 divisors (see below), whose sum is σ = 41317730160. Its totient is φ = 9837554760.

The previous prime is 21642620497. The next prime is 21642620533. The reversal of 21642620516 is 61502624612.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 245938826 + ... + 245938913.

It is an arithmetic number, because the mean of its divisors is an integer number (3443144180).

Almost surely, 2^21642620516 is an apocalyptic number.

It is an amenable number.

21642620516 is a deficient number, since it is larger than the sum of its proper divisors (19675109644).

21642620516 is a wasteful number, since it uses less digits than its factorization.

21642620516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 491877754 (or 491877752 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 35.

The spelling of 21642620516 in words is "twenty-one billion, six hundred forty-two million, six hundred twenty thousand, five hundred sixteen".