18531930 has 16 divisors (see below), whose sum is σ = 44476704. Its totient is φ = 4941840.

The previous prime is 18531917. The next prime is 18531937. The reversal of 18531930 is 3913581.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 617731 = 18531930 / (1 + 8 + 5 + 3 + 1 + 9 + 3 + 0).

It is not an unprimeable number, because it can be changed into a prime (18531937) 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, 308836 + ... + 308895.

It is an arithmetic number, because the mean of its divisors is an integer number (2779794).

Almost surely, 2^18531930 is an apocalyptic number.

18531930 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18531930 is an abundant number, since it is smaller than the sum of its proper divisors (25944774).

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

18531930 is a wasteful number, since it uses less digits than its factorization.

18531930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 617741.

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 18531930 is about 4304.8728204211. The cubic root of 18531930 is about 264.6306947821.

The spelling of 18531930 in words is "eighteen million, five hundred thirty-one thousand, nine hundred thirty".