20021304 has 16 divisors (see below), whose sum is σ = 50053320. Its totient is φ = 6673760.

The previous prime is 20021303. The next prime is 20021311. The reversal of 20021304 is 40312002.

It is a super-2 number, since 2×20021304² = 801705227720832, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a self number, because there is not a number n which added to its sum of digits gives 20021304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021303) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 417087 + ... + 417134.

Almost surely, 2^20021304 is an apocalyptic number.

20021304 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20021304 is an abundant number, since it is smaller than the sum of its proper divisors (30032016).

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

20021304 is a wasteful number, since it uses less digits than its factorization.

20021304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 834230 (or 834226 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 12.

The square root of 20021304 is about 4474.5171806576. The cubic root of 20021304 is about 271.5381073799.

Adding to 20021304 its reverse (40312002), we get a palindrome (60333306).

The spelling of 20021304 in words is "twenty million, twenty-one thousand, three hundred four".