20404037 has 4 divisors (see below), whose sum is σ = 20591340. Its totient is φ = 20216736.

The previous prime is 20404009. The next prime is 20404039. The reversal of 20404037 is 73040402.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11930116 + 8473921 = 3454^2 + 2911^2 .

It is a cyclic number.

It is not a de Polignac number, because 20404037 - 2¹⁰ = 20403013 is a prime.

It is a super-3 number, since 3×20404037³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20404039) 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, 93488 + ... + 93705.

It is an arithmetic number, because the mean of its divisors is an integer number (5147835).

Almost surely, 2^20404037 is an apocalyptic number.

It is an amenable number.

20404037 is a deficient number, since it is larger than the sum of its proper divisors (187303).

20404037 is a wasteful number, since it uses less digits than its factorization.

20404037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187302.

The product of its (nonzero) digits is 672, while the sum is 20.

The square root of 20404037 is about 4517.0827975586. The cubic root of 20404037 is about 273.2574644015.

Adding to 20404037 its reverse (73040402), we get a palindrome (93444439).

The spelling of 20404037 in words is "twenty million, four hundred four thousand, thirty-seven".