18727891240 has 32 divisors (see below), whose sum is σ = 42164284680. Its totient is φ = 7486440192.

The previous prime is 18727891229. The next prime is 18727891241. The reversal of 18727891240 is 4219872781.

It can be written as a sum of positive squares in 4 ways, for example, as 7132478116 + 11595413124 = 84454^2 + 107682^2 .

It is not an unprimeable number, because it can be changed into a prime (18727891241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82707 + ... + 210466.

Almost surely, 2^18727891240 is an apocalyptic number.

18727891240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18727891240 is an abundant number, since it is smaller than the sum of its proper divisors (23436393440).

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

18727891240 is a wasteful number, since it uses less digits than its factorization.

18727891240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294781 (or 294777 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 49.

The spelling of 18727891240 in words is "eighteen billion, seven hundred twenty-seven million, eight hundred ninety-one thousand, two hundred forty".