18500017397 has 2 divisors, whose sum is σ = 18500017398. Its totient is φ = 18500017396.

The previous prime is 18500017381. The next prime is 18500017411. The reversal of 18500017397 is 79371000581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18399837316 + 100180081 = 135646^2 + 10009^2 .

It is an emirp because it is prime and its reverse (79371000581) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18500017397 - 2⁴ = 18500017381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18500017897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9250008698 + 9250008699.

It is an arithmetic number, because the mean of its divisors is an integer number (9250008699).

Almost surely, 2^18500017397 is an apocalyptic number.

It is an amenable number.

18500017397 is a deficient number, since it is larger than the sum of its proper divisors (1).

18500017397 is an equidigital number, since it uses as much as digits as its factorization.

18500017397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 52920, while the sum is 41.

The spelling of 18500017397 in words is "eighteen billion, five hundred million, seventeen thousand, three hundred ninety-seven".