21426638791593 has 128 divisors (see below), whose sum is σ = 34548332363776. Its totient is φ = 11555828064000.

The previous prime is 21426638791573. The next prime is 21426638791651. The reversal of 21426638791593 is 39519783662412.

It is not a de Polignac number, because 21426638791593 - 2⁵ = 21426638791561 is a prime.

It is a Smith number, since the sum of its digits (66) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (21426638791573) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 2021947971 + ... + 2021958567.

It is an arithmetic number, because the mean of its divisors is an integer number (269908846592).

Almost surely, 2^{21426638791593} is an apocalyptic number.

It is an amenable number.

21426638791593 is a deficient number, since it is larger than the sum of its proper divisors (13121693572183).

21426638791593 is a wasteful number, since it uses less digits than its factorization.

21426638791593 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11163.

The product of its digits is 117573120, while the sum is 66.

The spelling of 21426638791593 in words is "twenty-one trillion, four hundred twenty-six billion, six hundred thirty-eight million, seven hundred ninety-one thousand, five hundred ninety-three".