21866857001667 has 24 divisors (see below), whose sum is σ = 31659534303488. Its totient is φ = 14543749584000.

The previous prime is 21866857001659. The next prime is 21866857001683. The reversal of 21866857001667 is 76610075866812.

It is not a de Polignac number, because 21866857001667 - 2³ = 21866857001659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21866847001667) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6582513 + ... + 9330765.

Almost surely, 2^{21866857001667} is an apocalyptic number.

21866857001667 is a deficient number, since it is larger than the sum of its proper divisors (9792677301821).

21866857001667 is a wasteful number, since it uses less digits than its factorization.

21866857001667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2750331 (or 2750328 counting only the distinct ones).

The product of its (nonzero) digits is 40642560, while the sum is 63.

The spelling of 21866857001667 in words is "twenty-one trillion, eight hundred sixty-six billion, eight hundred fifty-seven million, one thousand, six hundred sixty-seven".