20304140 has 12 divisors (see below), whose sum is σ = 42638736. Its totient is φ = 8121648.

The previous prime is 20304139. The next prime is 20304161. The reversal of 20304140 is 4140302.

It is a super-2 number, since 2×20304140² = 824516202279200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 507584 + ... + 507623.

It is an arithmetic number, because the mean of its divisors is an integer number (3553228).

Almost surely, 2^20304140 is an apocalyptic number.

20304140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20304140 is an abundant number, since it is smaller than the sum of its proper divisors (22334596).

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

20304140 is a wasteful number, since it uses less digits than its factorization.

20304140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1015216 (or 1015214 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 20304140 is about 4506.0115401539. The cubic root of 20304140 is about 272.8107836514.

Adding to 20304140 its reverse (4140302), we get a palindrome (24444442).

The spelling of 20304140 in words is "twenty million, three hundred four thousand, one hundred forty".