16133509 has 4 divisors (see below), whose sum is σ = 18438304. Its totient is φ = 13828716.

The previous prime is 16133503. The next prime is 16133519. The reversal of 16133509 is 90533161.

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, and also an emirpimes, since its reverse is a distinct semiprime: 90533161 = 1427 ⋅63443.

It is a cyclic number.

It is not a de Polignac number, because 16133509 - 2³ = 16133501 is a prime.

It is a super-2 number, since 2×16133509² = 520580225306162, 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 (16133501) 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, 1152387 + ... + 1152400.

It is an arithmetic number, because the mean of its divisors is an integer number (4609576).

Almost surely, 2^16133509 is an apocalyptic number.

It is an amenable number.

16133509 is a deficient number, since it is larger than the sum of its proper divisors (2304795).

16133509 is an equidigital number, since it uses as much as digits as its factorization.

16133509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2304794.

The product of its (nonzero) digits is 2430, while the sum is 28.

The square root of 16133509 is about 4016.6539557199. The cubic root of 16133509 is about 252.6831478479.

It can be divided in two parts, 161 and 33509, that added together give a triangular number (33670 = T₂₅₉).

The spelling of 16133509 in words is "sixteen million, one hundred thirty-three thousand, five hundred nine".