19972409523 has 32 divisors (see below), whose sum is σ = 31181075712. Its totient is φ = 11236377600.

The previous prime is 19972409521. The next prime is 19972409593. The reversal of 19972409523 is 32590427991.

It is not a de Polignac number, because 19972409523 - 2¹ = 19972409521 is a prime.

It is a super-3 number, since 3×19972409523³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (19972409521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 202893 + ... + 284798.

It is an arithmetic number, because the mean of its divisors is an integer number (974408616).

Almost surely, 2^19972409523 is an apocalyptic number.

19972409523 is a deficient number, since it is larger than the sum of its proper divisors (11208666189).

19972409523 is a wasteful number, since it uses less digits than its factorization.

19972409523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 487795.

The product of its (nonzero) digits is 1224720, while the sum is 51.

The spelling of 19972409523 in words is "nineteen billion, nine hundred seventy-two million, four hundred nine thousand, five hundred twenty-three".