21016648317 has 16 divisors (see below), whose sum is σ = 32430755840. Its totient is φ = 11857493232.

The previous prime is 21016648273. The next prime is 21016648321. The reversal of 21016648317 is 71384661012.

It is not a de Polignac number, because 21016648317 - 2⁷ = 21016648189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21016648517) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6332473 + ... + 6335790.

It is an arithmetic number, because the mean of its divisors is an integer number (2026922240).

Almost surely, 2^21016648317 is an apocalyptic number.

It is an amenable number.

21016648317 is a deficient number, since it is larger than the sum of its proper divisors (11414107523).

21016648317 is a wasteful number, since it uses less digits than its factorization.

21016648317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12668352.

The product of its (nonzero) digits is 48384, while the sum is 39.

The spelling of 21016648317 in words is "twenty-one billion, sixteen million, six hundred forty-eight thousand, three hundred seventeen".