16640906 has 4 divisors (see below), whose sum is σ = 24961362. Its totient is φ = 8320452.

The previous prime is 16640879. The next prime is 16640917. The reversal of 16640906 is 60904661.

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

It can be written as a sum of positive squares in only one way, i.e., 15721225 + 919681 = 3965^2 + 959^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4160225 + ... + 4160228.

Almost surely, 2^16640906 is an apocalyptic number.

16640906 is a deficient number, since it is larger than the sum of its proper divisors (8320456).

16640906 is an equidigital number, since it uses as much as digits as its factorization.

16640906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8320455.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 16640906 is about 4079.3266601242. The cubic root of 16640906 is about 255.3048053229.

The spelling of 16640906 in words is "sixteen million, six hundred forty thousand, nine hundred six".