16639973 has 16 divisors (see below), whose sum is σ = 20020224. Its totient is φ = 13530240.

The previous prime is 16639969. The next prime is 16639993. The reversal of 16639973 is 37993661.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 16639973 - 2² = 16639969 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16639943) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9836 + ... + 11402.

It is an arithmetic number, because the mean of its divisors is an integer number (1251264).

Almost surely, 2^16639973 is an apocalyptic number.

It is an amenable number.

16639973 is a deficient number, since it is larger than the sum of its proper divisors (3380251).

16639973 is a wasteful number, since it uses less digits than its factorization.

16639973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1652.

The product of its digits is 183708, while the sum is 44.

The square root of 16639973 is about 4079.2123014131. The cubic root of 16639973 is about 255.3000338713.

The spelling of 16639973 in words is "sixteen million, six hundred thirty-nine thousand, nine hundred seventy-three".