19886031509 has 2 divisors, whose sum is σ = 19886031510. Its totient is φ = 19886031508.

The previous prime is 19886031391. The next prime is 19886031527. The reversal of 19886031509 is 90513068891.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19853655409 + 32376100 = 140903^2 + 5690^2 .

It is a cyclic number.

It is not a de Polignac number, because 19886031509 - 2²⁰ = 19884982933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19886031709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9943015754 + 9943015755.

It is an arithmetic number, because the mean of its divisors is an integer number (9943015755).

Almost surely, 2^19886031509 is an apocalyptic number.

It is an amenable number.

19886031509 is a deficient number, since it is larger than the sum of its proper divisors (1).

19886031509 is an equidigital number, since it uses as much as digits as its factorization.

19886031509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 466560, while the sum is 50.

The spelling of 19886031509 in words is "nineteen billion, eight hundred eighty-six million, thirty-one thousand, five hundred nine".