20431316 has 6 divisors (see below), whose sum is σ = 35754810. Its totient is φ = 10215656.

The previous prime is 20431309. The next prime is 20431319. The reversal of 20431316 is 61313402.

It can be written as a sum of positive squares in only one way, i.e., 19536400 + 894916 = 4420^2 + 946^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20431319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2553911 + ... + 2553918.

It is an arithmetic number, because the mean of its divisors is an integer number (5959135).

Almost surely, 2^20431316 is an apocalyptic number.

It is an amenable number.

20431316 is a deficient number, since it is larger than the sum of its proper divisors (15323494).

20431316 is a wasteful number, since it uses less digits than its factorization.

20431316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5107833 (or 5107831 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 20431316 is about 4520.1013262979. The cubic root of 20431316 is about 273.3791865701.

Adding to 20431316 its reverse (61313402), we get a palindrome (81744718).

The spelling of 20431316 in words is "twenty million, four hundred thirty-one thousand, three hundred sixteen".