16742521 has 2 divisors, whose sum is σ = 16742522. Its totient is φ = 16742520.

The previous prime is 16742519. The next prime is 16742527. The reversal of 16742521 is 12524761.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11634921 + 5107600 = 3411^2 + 2260^2 .

It is an emirp because it is prime and its reverse (12524761) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16742521 - 2¹ = 16742519 is a prime.

Together with 16742519, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 16742521.

It is not a weakly prime, because it can be changed into another prime (16742527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8371260 + 8371261.

It is an arithmetic number, because the mean of its divisors is an integer number (8371261).

Almost surely, 2^16742521 is an apocalyptic number.

It is an amenable number.

16742521 is a deficient number, since it is larger than the sum of its proper divisors (1).

16742521 is an equidigital number, since it uses as much as digits as its factorization.

16742521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3360, while the sum is 28.

The square root of 16742521 is about 4091.7625786451. The cubic root of 16742521 is about 255.8234103203.

The spelling of 16742521 in words is "sixteen million, seven hundred forty-two thousand, five hundred twenty-one".