16431861 has 4 divisors (see below), whose sum is σ = 21909152. Its totient is φ = 10954572.

The previous prime is 16431853. The next prime is 16431887. The reversal of 16431861 is 16813461.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 16431861 - 2³ = 16431853 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16431851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2738641 + ... + 2738646.

It is an arithmetic number, because the mean of its divisors is an integer number (5477288).

Almost surely, 2^16431861 is an apocalyptic number.

It is an amenable number.

16431861 is a deficient number, since it is larger than the sum of its proper divisors (5477291).

16431861 is an equidigital number, since it uses as much as digits as its factorization.

16431861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5477290.

The product of its digits is 3456, while the sum is 30.

The square root of 16431861 is about 4053.6231941314. The cubic root of 16431861 is about 254.2312410443.

The spelling of 16431861 in words is "sixteen million, four hundred thirty-one thousand, eight hundred sixty-one".