16640407 has 4 divisors (see below), whose sum is σ = 19017616. Its totient is φ = 14263200.

The previous prime is 16640401. The next prime is 16640411. The reversal of 16640407 is 70404661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70404661 = 443 ⋅158927.

It is not a de Polignac number, because 16640407 - 2¹⁵ = 16607639 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 (16640401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1188594 + ... + 1188607.

It is an arithmetic number, because the mean of its divisors is an integer number (4754404).

Almost surely, 2^16640407 is an apocalyptic number.

16640407 is a deficient number, since it is larger than the sum of its proper divisors (2377209).

16640407 is an equidigital number, since it uses as much as digits as its factorization.

16640407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2377208.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 16640407 is about 4079.2654976111. The cubic root of 16640407 is about 255.3022534112.

The spelling of 16640407 in words is "sixteen million, six hundred forty thousand, four hundred seven".