16662505 has 4 divisors (see below), whose sum is σ = 19995012. Its totient is φ = 13330000.

The previous prime is 16662479. The next prime is 16662509. The reversal of 16662505 is 50526661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10810944 + 5851561 = 3288^2 + 2419^2 .

It is not a de Polignac number, because 16662505 - 2⁵ = 16662473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16662509) 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, 1666246 + ... + 1666255.

It is an arithmetic number, because the mean of its divisors is an integer number (4998753).

Almost surely, 2^16662505 is an apocalyptic number.

It is an amenable number.

16662505 is a deficient number, since it is larger than the sum of its proper divisors (3332507).

16662505 is an equidigital number, since it uses as much as digits as its factorization.

16662505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3332506.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 16662505 is about 4081.9731748261. The cubic root of 16662505 is about 255.4152148652.

The spelling of 16662505 in words is "sixteen million, six hundred sixty-two thousand, five hundred five".