21646064612 has 48 divisors (see below), whose sum is σ = 39773099520. Its totient is φ = 10288363008.

The previous prime is 21646064591. The next prime is 21646064689.

21646064612 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21646064612² (a number of 21 digits) contains 22 as substring.

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 15 ways as a sum of consecutive naturals, for example, 20954048 + ... + 20955080.

It is an arithmetic number, because the mean of its divisors is an integer number (828606240).

Almost surely, 2^21646064612 is an apocalyptic number.

It is an amenable number.

21646064612 is a deficient number, since it is larger than the sum of its proper divisors (18127034908).

21646064612 is a wasteful number, since it uses less digits than its factorization.

21646064612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2252 (or 2250 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 38.

The spelling of 21646064612 in words is "twenty-one billion, six hundred forty-six million, sixty-four thousand, six hundred twelve".