18219790 has 16 divisors (see below), whose sum is σ = 33352560. Its totient is φ = 7164160.

The previous prime is 18219787. The next prime is 18219791. The reversal of 18219790 is 9791281.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18219791) 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, 14851 + ... + 16030.

It is an arithmetic number, because the mean of its divisors is an integer number (2084535).

Almost surely, 2^18219790 is an apocalyptic number.

18219790 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18219790 is a deficient number, since it is larger than the sum of its proper divisors (15132770).

18219790 is a wasteful number, since it uses less digits than its factorization.

18219790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30947.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 18219790 is about 4268.4645951443. The cubic root of 18219790 is about 263.1365172880.

It can be divided in two parts, 1821 and 9790, that added together give a palindrome (11611).

The spelling of 18219790 in words is "eighteen million, two hundred nineteen thousand, seven hundred ninety".