16513231 has 4 divisors (see below), whose sum is σ = 18872272. Its totient is φ = 14154192.

The previous prime is 16513229. The next prime is 16513253. The reversal of 16513231 is 13231561.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16513231 - 2¹ = 16513229 is a prime.

It is a super-2 number, since 2×16513231² = 545373596118722, 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 (16513031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1179510 + ... + 1179523.

It is an arithmetic number, because the mean of its divisors is an integer number (4718068).

Almost surely, 2^16513231 is an apocalyptic number.

16513231 is a deficient number, since it is larger than the sum of its proper divisors (2359041).

16513231 is an equidigital number, since it uses as much as digits as its factorization.

16513231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2359040.

The product of its digits is 540, while the sum is 22.

The square root of 16513231 is about 4063.6474994763. The cubic root of 16513231 is about 254.6501983159.

Adding to 16513231 its reverse (13231561), we get a palindrome (29744792).

The spelling of 16513231 in words is "sixteen million, five hundred thirteen thousand, two hundred thirty-one".