18090857844 has 30 divisors (see below), whose sum is σ = 47293076754. Its totient is φ = 6030285840.

The previous prime is 18090857821. The next prime is 18090857867. The reversal of 18090857844 is 44875809081.

It is an interprime number because it is at equal distance from previous prime (18090857821) and next prime (18090857867).

It can be written as a sum of positive squares in only one way, i.e., 13726934244 + 4363923600 = 117162^2 + 66060^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 27917667 + ... + 27918314.

Almost surely, 2^18090857844 is an apocalyptic number.

It is an amenable number.

18090857844 is an abundant number, since it is smaller than the sum of its proper divisors (29202218910).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18090857844 is a wasteful number, since it uses less digits than its factorization.

18090857844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55835997 (or 55835986 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 54.

The spelling of 18090857844 in words is "eighteen billion, ninety million, eight hundred fifty-seven thousand, eight hundred forty-four".