18961610597 has 4 divisors (see below), whose sum is σ = 19044412620. Its totient is φ = 18878808576.

The previous prime is 18961610509. The next prime is 18961610639. The reversal of 18961610597 is 79501616981.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11615235076 + 7346375521 = 107774^2 + 85711^2 .

It is a cyclic number.

It is not a de Polignac number, because 18961610597 - 2¹⁸ = 18961348453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18961610797) 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, 41400668 + ... + 41401125.

It is an arithmetic number, because the mean of its divisors is an integer number (4761103155).

Almost surely, 2^18961610597 is an apocalyptic number.

It is an amenable number.

18961610597 is a deficient number, since it is larger than the sum of its proper divisors (82802023).

18961610597 is an equidigital number, since it uses as much as digits as its factorization.

18961610597 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82802022.

The product of its (nonzero) digits is 816480, while the sum is 53.

The spelling of 18961610597 in words is "eighteen billion, nine hundred sixty-one million, six hundred ten thousand, five hundred ninety-seven".