18957120409 has 2 divisors, whose sum is σ = 18957120410. Its totient is φ = 18957120408.

The previous prime is 18957120319. The next prime is 18957120521. The reversal of 18957120409 is 90402175981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18588595600 + 368524809 = 136340^2 + 19197^2 .

It is a cyclic number.

It is not a de Polignac number, because 18957120409 - 2¹¹ = 18957118361 is a prime.

It is not a weakly prime, because it can be changed into another prime (18957120109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9478560204 + 9478560205.

It is an arithmetic number, because the mean of its divisors is an integer number (9478560205).

Almost surely, 2^18957120409 is an apocalyptic number.

It is an amenable number.

18957120409 is a deficient number, since it is larger than the sum of its proper divisors (1).

18957120409 is an equidigital number, since it uses as much as digits as its factorization.

18957120409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 46.

The spelling of 18957120409 in words is "eighteen billion, nine hundred fifty-seven million, one hundred twenty thousand, four hundred nine".