18907690 has 8 divisors (see below), whose sum is σ = 34033860. Its totient is φ = 7563072.

The previous prime is 18907687. The next prime is 18907699. The reversal of 18907690 is 9670981.

It can be written as a sum of positive squares in 2 ways, for example, as 17114769 + 1792921 = 4137^2 + 1339^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×18907690² = 715001482272200, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (18907699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 945375 + ... + 945394.

Almost surely, 2^18907690 is an apocalyptic number.

18907690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18907690 is a deficient number, since it is larger than the sum of its proper divisors (15126170).

18907690 is a wasteful number, since it uses less digits than its factorization.

18907690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1890776.

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 18907690 is about 4348.2973679361. The cubic root of 18907690 is about 266.4073225118.

The spelling of 18907690 in words is "eighteen million, nine hundred seven thousand, six hundred ninety".