16007521 has 4 divisors (see below), whose sum is σ = 16157232. Its totient is φ = 15857812.

The previous prime is 16007483. The next prime is 16007527. The reversal of 16007521 is 12570061.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16007521 - 2⁷ = 16007393 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16007492 and 16007501.

It is not an unprimeable number, because it can be changed into a prime (16007527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74695 + ... + 74908.

It is an arithmetic number, because the mean of its divisors is an integer number (4039308).

Almost surely, 2^16007521 is an apocalyptic number.

It is an amenable number.

16007521 is a deficient number, since it is larger than the sum of its proper divisors (149711).

16007521 is a wasteful number, since it uses less digits than its factorization.

16007521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149710.

The product of its (nonzero) digits is 420, while the sum is 22.

The square root of 16007521 is about 4000.9400145466. The cubic root of 16007521 is about 252.0236865700.

Adding to 16007521 its reverse (12570061), we get a palindrome (28577582).

The spelling of 16007521 in words is "sixteen million, seven thousand, five hundred twenty-one".