16387661 has 4 divisors (see below), whose sum is σ = 17100192. Its totient is φ = 15675132.

The previous prime is 16387649. The next prime is 16387669. The reversal of 16387661 is 16678361.

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 16387661 - 2¹⁰ = 16386637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16387669) 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, 356231 + ... + 356276.

It is an arithmetic number, because the mean of its divisors is an integer number (4275048).

Almost surely, 2^16387661 is an apocalyptic number.

It is an amenable number.

16387661 is a deficient number, since it is larger than the sum of its proper divisors (712531).

16387661 is an equidigital number, since it uses as much as digits as its factorization.

16387661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 712530.

The product of its digits is 36288, while the sum is 38.

The square root of 16387661 is about 4048.1676101664. The cubic root of 16387661 is about 254.0030844687.

The spelling of 16387661 in words is "sixteen million, three hundred eighty-seven thousand, six hundred sixty-one".