16680401 has 4 divisors (see below), whose sum is σ = 16792500. Its totient is φ = 16568304.

The previous prime is 16680373. The next prime is 16680403. The reversal of 16680401 is 10408661.

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 672400 + 16008001 = 820^2 + 4001^2 .

It is a cyclic number.

It is not a de Polignac number, because 16680401 - 2¹⁴ = 16664017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16680403) 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, 55826 + ... + 56123.

It is an arithmetic number, because the mean of its divisors is an integer number (4198125).

Almost surely, 2^16680401 is an apocalyptic number.

It is an amenable number.

16680401 is a deficient number, since it is larger than the sum of its proper divisors (112099).

16680401 is a wasteful number, since it uses less digits than its factorization.

16680401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112098.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 16680401 is about 4084.1646636736. The cubic root of 16680401 is about 255.5066231945.

The spelling of 16680401 in words is "sixteen million, six hundred eighty thousand, four hundred one".