20680290 has 24 divisors (see below), whose sum is σ = 53768988. Its totient is φ = 5514720.

The previous prime is 20680271. The next prime is 20680333. The reversal of 20680290 is 9208602.

It can be written as a sum of positive squares in 2 ways, for example, as 19633761 + 1046529 = 4431^2 + 1023^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 114801 + ... + 114980.

Almost surely, 2^20680290 is an apocalyptic number.

20680290 is an abundant number, since it is smaller than the sum of its proper divisors (33088698).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20680290 is a wasteful number, since it uses less digits than its factorization.

20680290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229794 (or 229791 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 20680290 is about 4547.5586857126. The cubic root of 20680290 is about 274.4851634809.

Adding to 20680290 its reverse (9208602), we get a palindrome (29888892).

The spelling of 20680290 in words is "twenty million, six hundred eighty thousand, two hundred ninety".