16720857 has 16 divisors (see below), whose sum is σ = 24847360. Its totient is φ = 11113200.

The previous prime is 16720841. The next prime is 16720859. The reversal of 16720857 is 75802761.

It is not a de Polignac number, because 16720857 - 2⁴ = 16720841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16720859) 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, 10632 + ... + 12102.

It is an arithmetic number, because the mean of its divisors is an integer number (1552960).

Almost surely, 2^16720857 is an apocalyptic number.

It is an amenable number.

16720857 is a deficient number, since it is larger than the sum of its proper divisors (8126503).

16720857 is a wasteful number, since it uses less digits than its factorization.

16720857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1901 (or 1895 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 36.

The square root of 16720857 is about 4089.1144518098. The cubic root of 16720857 is about 255.7130217174.

The spelling of 16720857 in words is "sixteen million, seven hundred twenty thousand, eight hundred fifty-seven".