16662401 has 6 divisors (see below), whose sum is σ = 19382850. Its totient is φ = 14282016.

The previous prime is 16662343. The next prime is 16662403. The reversal of 16662401 is 10426661.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 14025025 + 2637376 = 3745^2 + 1624^2 .

It is a de Polignac number, because none of the positive numbers 2^k-16662401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16662403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 169976 + ... + 170073.

It is an arithmetic number, because the mean of its divisors is an integer number (3230475).

Almost surely, 2^16662401 is an apocalyptic number.

It is an amenable number.

16662401 is a deficient number, since it is larger than the sum of its proper divisors (2720449).

16662401 is an equidigital number, since it uses as much as digits as its factorization.

16662401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340063 (or 340056 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 16662401 is about 4081.9604358690. The cubic root of 16662401 is about 255.4146834677.

The spelling of 16662401 in words is "sixteen million, six hundred sixty-two thousand, four hundred one".