19218664431 has 12 divisors (see below), whose sum is σ = 28510571752. Its totient is φ = 12466160496.

The previous prime is 19218664429. The next prime is 19218664457. The reversal of 19218664431 is 13446681291.

19218664431 is a `hidden beast` number, since 192 + 18 + 6 + 6 + 443 + 1 = 666.

It is not a de Polignac number, because 19218664431 - 2¹ = 19218664429 is a prime.

It is a super-2 number, since 2×19218664431² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19218664831) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28856521 + ... + 28857186.

Almost surely, 2^19218664431 is an apocalyptic number.

19218664431 is a deficient number, since it is larger than the sum of its proper divisors (9291907321).

19218664431 is a wasteful number, since it uses less digits than its factorization.

19218664431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57713750 (or 57713747 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The spelling of 19218664431 in words is "nineteen billion, two hundred eighteen million, six hundred sixty-four thousand, four hundred thirty-one".