19972409522 has 18 divisors (see below), whose sum is σ = 32444613693.
Its totient is φ = 9216835992.
The previous prime is 19972409521. The next prime is 19972409593. The reversal of 19972409522 is 22590427991.
It can be written as a sum of positive squares in 2 ways, for example, as 17077001041 + 2895408481 = 130679^2 + 53809^2
It is an ABA number since it can be written as A⋅BA, here for A=2, B=99931.
It is a super-2 number, since 2×199724095222 (a number of 21 digits) contains 22 as substring.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (19972409521) by changing a digit.
It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2594363 + ... + 2602049.
Almost surely, 219972409522 is an apocalyptic number.
19972409522 is a deficient number, since it is larger than the sum of its proper divisors (12472204171).
19972409522 is an frugal number, since it uses more digits than its factorization.
19972409522 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 15402 (or 7702 counting only the distinct ones).
The product of its (nonzero) digits is 816480, while the sum is 50.
Multiplying 19972409522 by its sum of digits (50), we get a square (998620476100 = 9993102).
The spelling of 19972409522 in words is "nineteen billion, nine hundred seventy-two million, four hundred nine thousand, five hundred twenty-two".