16720538 has 8 divisors (see below), whose sum is σ = 25692660. Its totient is φ = 8156320.

The previous prime is 16720511. The next prime is 16720547. The reversal of 16720538 is 83502761.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 15311569 + 1408969 = 3913^2 + 1187^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon 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, 101873 + ... + 102036.

Almost surely, 2^16720538 is an apocalyptic number.

16720538 is a deficient number, since it is larger than the sum of its proper divisors (8972122).

16720538 is a wasteful number, since it uses less digits than its factorization.

16720538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203952.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 16720538 is about 4089.0754456234. The cubic root of 16720538 is about 255.7113955453.

The spelling of 16720538 in words is "sixteen million, seven hundred twenty thousand, five hundred thirty-eight".