19647242231 has 2 divisors, whose sum is σ = 19647242232. Its totient is φ = 19647242230.

The previous prime is 19647242213. The next prime is 19647242287. The reversal of 19647242231 is 13224274691.

Together with previous prime (19647242213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19647242231 is a prime.

It is a super-2 number, since 2×19647242231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19647242731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9823621115 + 9823621116.

It is an arithmetic number, because the mean of its divisors is an integer number (9823621116).

Almost surely, 2^19647242231 is an apocalyptic number.

19647242231 is a deficient number, since it is larger than the sum of its proper divisors (1).

19647242231 is an equidigital number, since it uses as much as digits as its factorization.

19647242231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145152, while the sum is 41.

The spelling of 19647242231 in words is "nineteen billion, six hundred forty-seven million, two hundred forty-two thousand, two hundred thirty-one".