21969754579 has 2 divisors, whose sum is σ = 21969754580. Its totient is φ = 21969754578.

The previous prime is 21969754553. The next prime is 21969754601. The reversal of 21969754579 is 97545796912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21969754579 - 2¹¹ = 21969752531 is a prime.

It is a super-2 number, since 2×21969754579² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21969754579.

It is not a weakly prime, because it can be changed into another prime (21969754519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10984877289 + 10984877290.

It is an arithmetic number, because the mean of its divisors is an integer number (10984877290).

Almost surely, 2^21969754579 is an apocalyptic number.

21969754579 is a deficient number, since it is larger than the sum of its proper divisors (1).

21969754579 is an equidigital number, since it uses as much as digits as its factorization.

21969754579 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42865200, while the sum is 64.

The spelling of 21969754579 in words is "twenty-one billion, nine hundred sixty-nine million, seven hundred fifty-four thousand, five hundred seventy-nine".