21786392747 has 16 divisors (see below), whose sum is σ = 25350247680. Its totient is φ = 18337179168.

The previous prime is 21786392743. The next prime is 21786392777. The reversal of 21786392747 is 74729368712.

It is a happy number.

It is not a de Polignac number, because 21786392747 - 2² = 21786392743 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21786392692 and 21786392701.

It is not an unprimeable number, because it can be changed into a prime (21786392743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75404 + ... + 221942.

It is an arithmetic number, because the mean of its divisors is an integer number (1584390480).

Almost surely, 2^21786392747 is an apocalyptic number.

21786392747 is a deficient number, since it is larger than the sum of its proper divisors (3563854933).

21786392747 is a wasteful number, since it uses less digits than its factorization.

21786392747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146930.

The product of its digits is 7112448, while the sum is 56.

The spelling of 21786392747 in words is "twenty-one billion, seven hundred eighty-six million, three hundred ninety-two thousand, seven hundred forty-seven".