20306490 has 16 divisors (see below), whose sum is σ = 48735648. Its totient is φ = 5415056.

The previous prime is 20306471. The next prime is 20306513. The reversal of 20306490 is 9460302.

It is a super-2 number, since 2×20306490² = 824707072240200, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20306490.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 338412 + ... + 338471.

It is an arithmetic number, because the mean of its divisors is an integer number (3045978).

Almost surely, 2^20306490 is an apocalyptic number.

20306490 is an abundant number, since it is smaller than the sum of its proper divisors (28429158).

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

20306490 is a wasteful number, since it uses less digits than its factorization.

20306490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 676893.

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 20306490 is about 4506.2722953679. The cubic root of 20306490 is about 272.8213082802.

Adding to 20306490 its reverse (9460302), we get a palindrome (29766792).

The spelling of 20306490 in words is "twenty million, three hundred six thousand, four hundred ninety".