21716853703505 has 16 divisors (see below), whose sum is σ = 26942713480704. Its totient is φ = 16786900131840.

The previous prime is 21716853703421. The next prime is 21716853703513. The reversal of 21716853703505 is 50530735861712.

It is not a de Polignac number, because 21716853703505 - 2³⁸ = 21441975796561 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 108849584 + ... + 109048913.

It is an arithmetic number, because the mean of its divisors is an integer number (1683919592544).

Almost surely, 2^{21716853703505} is an apocalyptic number.

It is an amenable number.

21716853703505 is a deficient number, since it is larger than the sum of its proper divisors (5225859777199).

21716853703505 is a wasteful number, since it uses less digits than its factorization.

21716853703505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217899176.

The product of its (nonzero) digits is 5292000, while the sum is 53.

The spelling of 21716853703505 in words is "twenty-one trillion, seven hundred sixteen billion, eight hundred fifty-three million, seven hundred three thousand, five hundred five".