21797929767 has 4 divisors (see below), whose sum is σ = 29063906360. Its totient is φ = 14531953176.

The previous prime is 21797929739. The next prime is 21797929799. The reversal of 21797929767 is 76792979712.

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

It is not a de Polignac number, because 21797929767 - 2⁸ = 21797929511 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21797929698 and 21797929707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21797929717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3632988292 + ... + 3632988297.

It is an arithmetic number, because the mean of its divisors is an integer number (7265976590).

Almost surely, 2^21797929767 is an apocalyptic number.

21797929767 is a deficient number, since it is larger than the sum of its proper divisors (7265976593).

21797929767 is an equidigital number, since it uses as much as digits as its factorization.

21797929767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7265976592.

The product of its digits is 42007896, while the sum is 66.

The spelling of 21797929767 in words is "twenty-one billion, seven hundred ninety-seven million, nine hundred twenty-nine thousand, seven hundred sixty-seven".