16730521 has 4 divisors (see below), whose sum is σ = 16745344. Its totient is φ = 16715700.

The previous prime is 16730509. The next prime is 16730587. The reversal of 16730521 is 12503761.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12503761 = 1087 ⋅11503.

It is a cyclic number.

It is not a de Polignac number, because 16730521 - 2⁵ = 16730489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16730921) 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, 5565 + ... + 8026.

It is an arithmetic number, because the mean of its divisors is an integer number (4186336).

Almost surely, 2^16730521 is an apocalyptic number.

It is an amenable number.

16730521 is a deficient number, since it is larger than the sum of its proper divisors (14823).

16730521 is a wasteful number, since it uses less digits than its factorization.

16730521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14822.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 16730521 is about 4090.2959550624. The cubic root of 16730521 is about 255.7622762643.

The spelling of 16730521 in words is "sixteen million, seven hundred thirty thousand, five hundred twenty-one".