20320404 has 24 divisors (see below), whose sum is σ = 51061920. Its totient is φ = 6252384.

The previous prime is 20320373. The next prime is 20320409. The reversal of 20320404 is 40402302.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20320409) 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, 64974 + ... + 65285.

It is an arithmetic number, because the mean of its divisors is an integer number (2127580).

Almost surely, 2^20320404 is an apocalyptic number.

It is an amenable number.

20320404 is an abundant number, since it is smaller than the sum of its proper divisors (30741516).

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

20320404 is a wasteful number, since it uses less digits than its factorization.

20320404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130279 (or 130277 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 15.

The square root of 20320404 is about 4507.8158791149. The cubic root of 20320404 is about 272.8836064091.

Adding to 20320404 its reverse (40402302), we get a palindrome (60722706).

The spelling of 20320404 in words is "twenty million, three hundred twenty thousand, four hundred four".