21668014475 has 6 divisors (see below), whose sum is σ = 26868337980. Its totient is φ = 17334411560.

The previous prime is 21668014463. The next prime is 21668014507. The reversal of 21668014475 is 57441086612.

It is not a de Polignac number, because 21668014475 - 2²⁰ = 21666965899 is a prime.

It is a super-3 number, since 3×21668014475³ (a number of 32 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 433360265 + ... + 433360314.

It is an arithmetic number, because the mean of its divisors is an integer number (4478056330).

Almost surely, 2^21668014475 is an apocalyptic number.

21668014475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21668014475 is a deficient number, since it is larger than the sum of its proper divisors (5200323505).

21668014475 is an equidigital number, since it uses as much as digits as its factorization.

21668014475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 866720589 (or 866720584 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 21668014475 in words is "twenty-one billion, six hundred sixty-eight million, fourteen thousand, four hundred seventy-five".