16520257 has 12 divisors (see below), whose sum is σ = 18168240. Its totient is φ = 15011568.

The previous prime is 16520239. The next prime is 16520263. The reversal of 16520257 is 75202561.

It is not a de Polignac number, because 16520257 - 2¹⁵ = 16487489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16523257) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10594 + ... + 12052.

It is an arithmetic number, because the mean of its divisors is an integer number (1514020).

Almost surely, 2^16520257 is an apocalyptic number.

It is an amenable number.

16520257 is a deficient number, since it is larger than the sum of its proper divisors (1647983).

16520257 is a wasteful number, since it uses less digits than its factorization.

16520257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1552 (or 1539 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 16520257 is about 4064.5119018155. The cubic root of 16520257 is about 254.6863091291.

It can be divided in two parts, 165 and 20257, that multiplied together give a triangular number (3342405 = T₂₅₈₅).

The spelling of 16520257 in words is "sixteen million, five hundred twenty thousand, two hundred fifty-seven".