21774712991 has 8 divisors (see below), whose sum is σ = 21949538304. Its totient is φ = 21599940600.

The previous prime is 21774712957. The next prime is 21774712997. The reversal of 21774712991 is 19921747712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21774712991 - 2¹⁴ = 21774696607 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 (21774712997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1489166 + ... + 1503716.

It is an arithmetic number, because the mean of its divisors is an integer number (2743692288).

Almost surely, 2^21774712991 is an apocalyptic number.

21774712991 is a deficient number, since it is larger than the sum of its proper divisors (174825313).

21774712991 is a wasteful number, since it uses less digits than its factorization.

21774712991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26461.

The product of its digits is 444528, while the sum is 50.

The spelling of 21774712991 in words is "twenty-one billion, seven hundred seventy-four million, seven hundred twelve thousand, nine hundred ninety-one".