20402304 has 128 divisors (see below), whose sum is σ = 60204480. Its totient is φ = 6082560.

The previous prime is 20402287. The next prime is 20402321. The reversal of 20402304 is 40320402.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20402287) and next prime (20402321).

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 304479 + ... + 304545.

Almost surely, 2^20402304 is an apocalyptic number.

20402304 is a gapful number since it is divisible by the number (24) 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 20402304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30102240).

20402304 is an abundant number, since it is smaller than the sum of its proper divisors (39802176).

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

20402304 is a wasteful number, since it uses less digits than its factorization.

20402304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158 (or 146 counting only the distinct ones).

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

The square root of 20402304 is about 4516.8909661403. The cubic root of 20402304 is about 273.2497278835.

Adding to 20402304 its reverse (40320402), we get a palindrome (60722706).

It can be divided in two parts, 20402 and 304, that added together give a triangular number (20706 = T₂₀₃).

The spelling of 20402304 in words is "twenty million, four hundred two thousand, three hundred four".