20440307 has 16 divisors (see below), whose sum is σ = 22980672. Its totient is φ = 18078720.

The previous prime is 20440297. The next prime is 20440309. The reversal of 20440307 is 70304402.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20440307 - 2⁴ = 20440291 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20440309) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23423 + ... + 24279.

It is an arithmetic number, because the mean of its divisors is an integer number (1436292).

Almost surely, 2^20440307 is an apocalyptic number.

20440307 is a deficient number, since it is larger than the sum of its proper divisors (2540365).

20440307 is a wasteful number, since it uses less digits than its factorization.

20440307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 958.

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

The square root of 20440307 is about 4521.0957742565. The cubic root of 20440307 is about 273.4192817489.

Adding to 20440307 its reverse (70304402), we get a palindrome (90744709).

The spelling of 20440307 in words is "twenty million, four hundred forty thousand, three hundred seven".