18561740 has 24 divisors (see below), whose sum is σ = 40325040. Its totient is φ = 7168448.

The previous prime is 18561737. The next prime is 18561749. The reversal of 18561740 is 4716581.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 18561697 and 18561706.

It is not an unprimeable number, because it can be changed into a prime (18561749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15422 + ... + 16581.

It is an arithmetic number, because the mean of its divisors is an integer number (1680210).

Almost surely, 2^18561740 is an apocalyptic number.

18561740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18561740 is an abundant number, since it is smaller than the sum of its proper divisors (21763300).

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

18561740 is a wasteful number, since it uses less digits than its factorization.

18561740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32041 (or 32039 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 18561740 is about 4308.3337846550. Note that the first 3 decimals coincide. The cubic root of 18561740 is about 264.7725115449.

The spelling of 18561740 in words is "eighteen million, five hundred sixty-one thousand, seven hundred forty".