20440031 has 6 divisors (see below), whose sum is σ = 21367920. Its totient is φ = 19550828.

The previous prime is 20439959. The next prime is 20440039. The reversal of 20440031 is 13004402.

It is not a de Polignac number, because 20440031 - 2¹⁰ = 20439007 is a prime.

It is a super-2 number, since 2×20440031² = 835589734561922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20439988 and 20440015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20440039) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 18791 + ... + 19848.

It is an arithmetic number, because the mean of its divisors is an integer number (3561320).

Almost surely, 2^20440031 is an apocalyptic number.

20440031 is a deficient number, since it is larger than the sum of its proper divisors (927889).

20440031 is an equidigital number, since it uses as much as digits as its factorization.

20440031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38685 (or 38662 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 20440031 is about 4521.0652505798. The cubic root of 20440031 is about 273.4180511076.

Adding to 20440031 its reverse (13004402), we get a palindrome (33444433).

The spelling of 20440031 in words is "twenty million, four hundred forty thousand, thirty-one".