20306900 has 36 divisors (see below), whose sum is σ = 44801820. Its totient is φ = 7987200.

The previous prime is 20306887. The next prime is 20306903. The reversal of 20306900 is 960302.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 4656964 + 15649936 = 2158^2 + 3956^2 .

It is a super-2 number, since 2×20306900² = 824740375220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20306903) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4436 + ... + 7764.

It is an arithmetic number, because the mean of its divisors is an integer number (1244495).

Almost surely, 2^20306900 is an apocalyptic number.

20306900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20306900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22400910).

20306900 is an abundant number, since it is smaller than the sum of its proper divisors (24494920).

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

20306900 is a wasteful number, since it uses less digits than its factorization.

20306900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3404 (or 3397 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 20306900 is about 4506.3177872849. The cubic root of 20306900 is about 272.8231444088.

The spelling of 20306900 in words is "twenty million, three hundred six thousand, nine hundred".