21064646012 has 12 divisors (see below), whose sum is σ = 36907710840. Its totient is φ = 10519585776.

The previous prime is 21064646011. The next prime is 21064646021.

21064646012 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21064646012² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21064646012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21064646011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3180587 + ... + 3187202.

It is an arithmetic number, because the mean of its divisors is an integer number (3075642570).

Almost surely, 2^21064646012 is an apocalyptic number.

It is an amenable number.

21064646012 is a deficient number, since it is larger than the sum of its proper divisors (15843064828).

21064646012 is a wasteful number, since it uses less digits than its factorization.

21064646012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6368620 (or 6368618 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 32.

The spelling of 21064646012 in words is "twenty-one billion, sixty-four million, six hundred forty-six thousand, twelve".