21744642212477 has 4 divisors (see below), whose sum is σ = 21744937525056. Its totient is φ = 21744346899900.

The previous prime is 21744642212459. The next prime is 21744642212507. The reversal of 21744642212477 is 77421224644712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21744642212477 - 2⁸ = 21744642212221 is a prime.

It is a super-2 number, since 2×21744642212477² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21744642212407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 147545813 + ... + 147693114.

It is an arithmetic number, because the mean of its divisors is an integer number (5436234381264).

Almost surely, 2^{21744642212477} is an apocalyptic number.

It is an amenable number.

21744642212477 is a deficient number, since it is larger than the sum of its proper divisors (295312579).

21744642212477 is an equidigital number, since it uses as much as digits as its factorization.

21744642212477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295312578.

The product of its digits is 8429568, while the sum is 53.

The spelling of 21744642212477 in words is "twenty-one trillion, seven hundred forty-four billion, six hundred forty-two million, two hundred twelve thousand, four hundred seventy-seven".