21979077122 has 6 divisors (see below), whose sum is σ = 32968930179. Its totient is φ = 10989433730.

The previous prime is 21979077053. The next prime is 21979077137. The reversal of 21979077122 is 22177097912.

It can be written as a sum of positive squares in only one way, i.e., 10989538561 + 10989538561 = 104831^2 + 104831^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=104831.

It is a super-2 number, since 2×21979077122² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 2 ways as a sum of consecutive naturals, for example, 157247 + ... + 262077.

Almost surely, 2^21979077122 is an apocalyptic number.

21979077122 is a deficient number, since it is larger than the sum of its proper divisors (10989853057).

21979077122 is an frugal number, since it uses more digits than its factorization.

21979077122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209664 (or 104833 counting only the distinct ones).

The product of its (nonzero) digits is 222264, while the sum is 47.

The spelling of 21979077122 in words is "twenty-one billion, nine hundred seventy-nine million, seventy-seven thousand, one hundred twenty-two".