21645793016 has 32 divisors (see below), whose sum is σ = 42734682000. Its totient is φ = 10250217216.

The previous prime is 21645793003. The next prime is 21645793019. The reversal of 21645793016 is 61039754612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21645793019) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 539540 + ... + 578268.

Almost surely, 2^21645793016 is an apocalyptic number.

It is an amenable number.

21645793016 is a deficient number, since it is larger than the sum of its proper divisors (21088888984).

21645793016 is a wasteful number, since it uses less digits than its factorization.

21645793016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42431 (or 42427 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 44.

The spelling of 21645793016 in words is "twenty-one billion, six hundred forty-five million, seven hundred ninety-three thousand, sixteen".