18420580 has 12 divisors (see below), whose sum is σ = 38683260. Its totient is φ = 7368224.

The previous prime is 18420559. The next prime is 18420581. The reversal of 18420580 is 8502481.

It can be written as a sum of positive squares in 2 ways, for example, as 2802276 + 15618304 = 1674^2 + 3952^2 .

It is not an unprimeable number, because it can be changed into a prime (18420581) 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, 460495 + ... + 460534.

It is an arithmetic number, because the mean of its divisors is an integer number (3223605).

Almost surely, 2^18420580 is an apocalyptic number.

18420580 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18420580 is an abundant number, since it is smaller than the sum of its proper divisors (20262680).

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

18420580 is a wasteful number, since it uses less digits than its factorization.

18420580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 921038 (or 921036 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 18420580 is about 4291.9203161289. The cubic root of 18420580 is about 264.0996142294.

The spelling of 18420580 in words is "eighteen million, four hundred twenty thousand, five hundred eighty".