20090645 has 8 divisors (see below), whose sum is σ = 24146304. Its totient is φ = 16047504.

The previous prime is 20090627. The next prime is 20090647. The reversal of 20090645 is 54609002.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20090645 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20090647) 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, 872 + ... + 6398.

It is an arithmetic number, because the mean of its divisors is an integer number (3018288).

Almost surely, 2^20090645 is an apocalyptic number.

It is an amenable number.

20090645 is a deficient number, since it is larger than the sum of its proper divisors (4055659).

20090645 is an equidigital number, since it uses as much as digits as its factorization.

20090645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6259.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 20090645 is about 4482.2589171086. The cubic root of 20090645 is about 271.8512243268.

Adding to 20090645 its reverse (54609002), we get a palindrome (74699647).

The spelling of 20090645 in words is "twenty million, ninety thousand, six hundred forty-five".