18920290 has 8 divisors (see below), whose sum is σ = 34056540. Its totient is φ = 7568112.

The previous prime is 18920287. The next prime is 18920327. The reversal of 18920290 is 9202981.

It can be written as a sum of positive squares in 2 ways, for example, as 17918289 + 1002001 = 4233^2 + 1001^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 946005 + ... + 946024.

Almost surely, 2^18920290 is an apocalyptic number.

18920290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18920290 is a deficient number, since it is larger than the sum of its proper divisors (15136250).

18920290 is a wasteful number, since it uses less digits than its factorization.

18920290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1892036.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 18920290 is about 4349.7459695941. The cubic root of 18920290 is about 266.4664869206.

The spelling of 18920290 in words is "eighteen million, nine hundred twenty thousand, two hundred ninety".