16721473 has 2 divisors, whose sum is σ = 16721474. Its totient is φ = 16721472.

The previous prime is 16721461. The next prime is 16721479. The reversal of 16721473 is 37412761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15000129 + 1721344 = 3873^2 + 1312^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16721473 is a prime.

It is not a weakly prime, because it can be changed into another prime (16721479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8360736 + 8360737.

It is an arithmetic number, because the mean of its divisors is an integer number (8360737).

Almost surely, 2^16721473 is an apocalyptic number.

It is an amenable number.

16721473 is a deficient number, since it is larger than the sum of its proper divisors (1).

16721473 is an equidigital number, since it uses as much as digits as its factorization.

16721473 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7056, while the sum is 31.

The square root of 16721473 is about 4089.1897730480. The cubic root of 16721473 is about 255.7161618532.

The spelling of 16721473 in words is "sixteen million, seven hundred twenty-one thousand, four hundred seventy-three".