21790667808707 has 16 divisors (see below), whose sum is σ = 25986582561792. Its totient is φ = 17865505864800.

The previous prime is 21790667808671. The next prime is 21790667808841. The reversal of 21790667808707 is 70780876609712.

It is a cyclic number.

It is not a de Polignac number, because 21790667808707 - 2¹⁸ = 21790667546563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21790667804707) 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, 24761957 + ... + 25626857.

It is an arithmetic number, because the mean of its divisors is an integer number (1624161410112).

Almost surely, 2^{21790667808707} is an apocalyptic number.

21790667808707 is a deficient number, since it is larger than the sum of its proper divisors (4195914753085).

21790667808707 is a wasteful number, since it uses less digits than its factorization.

21790667808707 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1021418.

The product of its (nonzero) digits is 99574272, while the sum is 68.

The spelling of 21790667808707 in words is "twenty-one trillion, seven hundred ninety billion, six hundred sixty-seven million, eight hundred eight thousand, seven hundred seven".