16621705 has 4 divisors (see below), whose sum is σ = 19946052. Its totient is φ = 13297360.

The previous prime is 16621681. The next prime is 16621721. The reversal of 16621705 is 50712661.

16621705 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 7639696 + 8982009 = 2764^2 + 2997^2 .

It is not a de Polignac number, because 16621705 - 2⁹ = 16621193 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1662166 + ... + 1662175.

It is an arithmetic number, because the mean of its divisors is an integer number (4986513).

Almost surely, 2^16621705 is an apocalyptic number.

It is an amenable number.

16621705 is a deficient number, since it is larger than the sum of its proper divisors (3324347).

16621705 is an equidigital number, since it uses as much as digits as its factorization.

16621705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3324346.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 16621705 is about 4076.9725287277. The cubic root of 16621705 is about 255.2065736081.

The spelling of 16621705 in words is "sixteen million, six hundred twenty-one thousand, seven hundred five".