16661249 has 4 divisors (see below), whose sum is σ = 18175920. Its totient is φ = 15146580.

The previous prime is 16661243. The next prime is 16661251. The reversal of 16661249 is 94216661.

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 a cyclic number.

It is not a de Polignac number, because 16661249 - 2¹² = 16657153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16661243) 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, 757319 + ... + 757340.

It is an arithmetic number, because the mean of its divisors is an integer number (4543980).

Almost surely, 2^16661249 is an apocalyptic number.

It is an amenable number.

16661249 is a deficient number, since it is larger than the sum of its proper divisors (1514671).

16661249 is a wasteful number, since it uses less digits than its factorization.

16661249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1514670.

The product of its digits is 15552, while the sum is 35.

The square root of 16661249 is about 4081.8193247619. The cubic root of 16661249 is about 255.4087970712.

It can be divided in two parts, 166612 and 49, that added together give a palindrome (166661).

The spelling of 16661249 in words is "sixteen million, six hundred sixty-one thousand, two hundred forty-nine".