21658770668471 has 8 divisors (see below), whose sum is σ = 22189180172544. Its totient is φ = 21128463393280.

The previous prime is 21658770668443. The next prime is 21658770668477. The reversal of 21658770668471 is 17486607785612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21658770668471 - 2³⁴ = 21641590799287 is a prime.

It is a super-3 number, since 3×21658770668471³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21658770668477) 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, 25128215 + ... + 25975848.

It is an arithmetic number, because the mean of its divisors is an integer number (2773647521568).

Almost surely, 2^{21658770668471} is an apocalyptic number.

21658770668471 is a deficient number, since it is larger than the sum of its proper divisors (530409504073).

21658770668471 is a wasteful number, since it uses less digits than its factorization.

21658770668471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51114441.

The product of its (nonzero) digits is 189665280, while the sum is 68.

The spelling of 21658770668471 in words is "twenty-one trillion, six hundred fifty-eight billion, seven hundred seventy million, six hundred sixty-eight thousand, four hundred seventy-one".