16311431 has 4 divisors (see below), whose sum is σ = 16320864. Its totient is φ = 16302000.

The previous prime is 16311419. The next prime is 16311467. The reversal of 16311431 is 13411361.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 13411361 = 1627 ⋅8243.

It is a cyclic number.

It is not a de Polignac number, because 16311431 - 2¹⁸ = 16049287 is a prime.

It is a super-2 number, since 2×16311431² = 532125562535522, which contains 22 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 (16311731) 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 in 3 ways as a sum of consecutive naturals, for example, 1295 + ... + 5856.

It is an arithmetic number, because the mean of its divisors is an integer number (4080216).

Almost surely, 2^16311431 is an apocalyptic number.

16311431 is a deficient number, since it is larger than the sum of its proper divisors (9433).

16311431 is an equidigital number, since it uses as much as digits as its factorization.

16311431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9432.

The product of its digits is 216, while the sum is 20.

The square root of 16311431 is about 4038.7412643050. The cubic root of 16311431 is about 253.6086259824.

Adding to 16311431 its reverse (13411361), we get a palindrome (29722792).

The spelling of 16311431 in words is "sixteen million, three hundred eleven thousand, four hundred thirty-one".