20306290 has 16 divisors (see below), whose sum is σ = 37151640. Its totient is φ = 7989120.

The previous prime is 20306257. The next prime is 20306291. The reversal of 20306290 is 9260302.

It can be written as a sum of positive squares in 4 ways, for example, as 4695889 + 15610401 = 2167^2 + 3951^2 .

It is not an unprimeable number, because it can be changed into a prime (20306291) 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, 16035 + ... + 17254.

Almost surely, 2^20306290 is an apocalyptic number.

20306290 is a deficient number, since it is larger than the sum of its proper divisors (16845350).

20306290 is a wasteful number, since it uses less digits than its factorization.

20306290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33357.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 20306290 is about 4506.2501040222. The cubic root of 20306290 is about 272.8204125987.

Adding to 20306290 its reverse (9260302), we get a palindrome (29566592).

The spelling of 20306290 in words is "twenty million, three hundred six thousand, two hundred ninety".