21608146660 has 24 divisors (see below), whose sum is σ = 45380301120. Its totient is φ = 8642650464.

The previous prime is 21608146627. The next prime is 21608146687. The reversal of 21608146660 is 6664180612.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 349827 + ... + 406933.

It is an arithmetic number, because the mean of its divisors is an integer number (1890845880).

Almost surely, 2^21608146660 is an apocalyptic number.

21608146660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21608146660 is an abundant number, since it is smaller than the sum of its proper divisors (23772154460).

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

21608146660 is a wasteful number, since it uses less digits than its factorization.

21608146660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76035 (or 76033 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 40.

The spelling of 21608146660 in words is "twenty-one billion, six hundred eight million, one hundred forty-six thousand, six hundred sixty".