18378145957 has 4 divisors (see below), whose sum is σ = 18471436236. Its totient is φ = 18284855680.

The previous prime is 18378145943. The next prime is 18378145969. The reversal of 18378145957 is 75954187381.

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 8028339201 + 10349806756 = 89601^2 + 101734^2 .

It is a cyclic number.

It is not a de Polignac number, because 18378145957 - 2⁷ = 18378145829 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 (18378145937) 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, 46644844 + ... + 46645237.

It is an arithmetic number, because the mean of its divisors is an integer number (4617859059).

Almost surely, 2^18378145957 is an apocalyptic number.

It is an amenable number.

18378145957 is a deficient number, since it is larger than the sum of its proper divisors (93290279).

18378145957 is an equidigital number, since it uses as much as digits as its factorization.

18378145957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93290278.

The product of its digits is 8467200, while the sum is 58.

The spelling of 18378145957 in words is "eighteen billion, three hundred seventy-eight million, one hundred forty-five thousand, nine hundred fifty-seven".