15812197993 has 16 divisors (see below), whose sum is σ = 17295216640. Its totient is φ = 14400666000.

The previous prime is 15812197969. The next prime is 15812198023. The reversal of 15812197993 is 39979121851.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 15812197993 - 2³³ = 7222263401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15812197903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46 + ... + 177832.

It is an arithmetic number, because the mean of its divisors is an integer number (1080951040).

Almost surely, 2^15812197993 is an apocalyptic number.

It is an amenable number.

15812197993 is a deficient number, since it is larger than the sum of its proper divisors (1483018647).

15812197993 is a wasteful number, since it uses less digits than its factorization.

15812197993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177988.

The product of its digits is 1224720, while the sum is 55.

The spelling of 15812197993 in words is "fifteen billion, eight hundred twelve million, one hundred ninety-seven thousand, nine hundred ninety-three".