18819690 has 64 divisors (see below), whose sum is σ = 48090240. Its totient is φ = 4700160.

The previous prime is 18819679. The next prime is 18819701. The reversal of 18819690 is 9691881.

It is an interprime number because it is at equal distance from previous prime (18819679) and next prime (18819701).

It is a super-2 number, since 2×18819690² = 708361463392200, which contains 22 as substring.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 77970 + ... + 78210.

It is an arithmetic number, because the mean of its divisors is an integer number (751410).

Almost surely, 2^18819690 is an apocalyptic number.

18819690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18819690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24045120).

18819690 is an abundant number, since it is smaller than the sum of its proper divisors (29270550).

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

18819690 is a wasteful number, since it uses less digits than its factorization.

18819690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407.

The product of its (nonzero) digits is 31104, while the sum is 42.

The square root of 18819690 is about 4338.1666634651. The cubic root of 18819690 is about 265.9933761329.

The spelling of 18819690 in words is "eighteen million, eight hundred nineteen thousand, six hundred ninety".