21772742799 has 4 divisors (see below), whose sum is σ = 29030323736. Its totient is φ = 14515161864.

The previous prime is 21772742791. The next prime is 21772742861. The reversal of 21772742799 is 99724727712.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21772742799 - 2³ = 21772742791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21772742791) 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, 3628790464 + ... + 3628790469.

It is an arithmetic number, because the mean of its divisors is an integer number (7257580934).

Almost surely, 2^21772742799 is an apocalyptic number.

21772742799 is a deficient number, since it is larger than the sum of its proper divisors (7257580937).

21772742799 is an equidigital number, since it uses as much as digits as its factorization.

21772742799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7257580936.

The product of its digits is 6223392, while the sum is 57.

The spelling of 21772742799 in words is "twenty-one billion, seven hundred seventy-two million, seven hundred forty-two thousand, seven hundred ninety-nine".