16521713 has 4 divisors (see below), whose sum is σ = 17792628. Its totient is φ = 15250800.

The previous prime is 16521709. The next prime is 16521727. The reversal of 16521713 is 31712561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31712561 = 23 ⋅1378807.

It can be written as a sum of positive squares in 2 ways, for example, as 10679824 + 5841889 = 3268^2 + 2417^2 .

It is a cyclic number.

It is not a de Polignac number, because 16521713 - 2² = 16521709 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16521413) 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, 635438 + ... + 635463.

It is an arithmetic number, because the mean of its divisors is an integer number (4448157).

Almost surely, 2^16521713 is an apocalyptic number.

16521713 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

16521713 is a deficient number, since it is larger than the sum of its proper divisors (1270915).

16521713 is a wasteful number, since it uses less digits than its factorization.

16521713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1270914.

The product of its digits is 1260, while the sum is 26.

The square root of 16521713 is about 4064.6910091666. The cubic root of 16521713 is about 254.6937911026.

The spelling of 16521713 in words is "sixteen million, five hundred twenty-one thousand, seven hundred thirteen".