21424800664145 has 32 divisors (see below), whose sum is σ = 26242921717632. Its totient is φ = 16785598781952.

The previous prime is 21424800664129. The next prime is 21424800664177. The reversal of 21424800664145 is 54146600842412.

It is a cyclic number.

It is not a de Polignac number, because 21424800664145 - 2⁴ = 21424800664129 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21424800664145.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 968429054 + ... + 968451176.

It is an arithmetic number, because the mean of its divisors is an integer number (820091303676).

Almost surely, 2^{21424800664145} is an apocalyptic number.

It is an amenable number.

21424800664145 is a deficient number, since it is larger than the sum of its proper divisors (4818121053487).

21424800664145 is a wasteful number, since it uses less digits than its factorization.

21424800664145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28721.

The product of its (nonzero) digits is 1474560, while the sum is 47.

The spelling of 21424800664145 in words is "twenty-one trillion, four hundred twenty-four billion, eight hundred million, six hundred sixty-four thousand, one hundred forty-five".