18856197361 has 4 divisors (see below), whose sum is σ = 19464461824. Its totient is φ = 18247932900.

The previous prime is 18856197359. The next prime is 18856197389. The reversal of 18856197361 is 16379165881.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18856197361 - 2¹ = 18856197359 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18856197391) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 304132185 + ... + 304132246.

It is an arithmetic number, because the mean of its divisors is an integer number (4866115456).

Almost surely, 2^18856197361 is an apocalyptic number.

It is an amenable number.

18856197361 is a deficient number, since it is larger than the sum of its proper divisors (608264463).

18856197361 is an equidigital number, since it uses as much as digits as its factorization.

18856197361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 608264462.

The product of its digits is 2177280, while the sum is 55.

The spelling of 18856197361 in words is "eighteen billion, eight hundred fifty-six million, one hundred ninety-seven thousand, three hundred sixty-one".