20900890 has 8 divisors (see below), whose sum is σ = 37621620. Its totient is φ = 8360352.

The previous prime is 20900879. The next prime is 20900897. The reversal of 20900890 is 9800902.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18344089 + 2556801 = 4283^2 + 1599^2 .

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

It is not an unprimeable number, because it can be changed into a prime (20900897) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1045035 + ... + 1045054.

Almost surely, 2^20900890 is an apocalyptic number.

20900890 is a deficient number, since it is larger than the sum of its proper divisors (16720730).

20900890 is a wasteful number, since it uses less digits than its factorization.

20900890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2090096.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 20900890 is about 4571.7491182260. The cubic root of 20900890 is about 275.4577060974.

The spelling of 20900890 in words is "twenty million, nine hundred thousand, eight hundred ninety".