16750021 has 2 divisors, whose sum is σ = 16750022. Its totient is φ = 16750020.

The previous prime is 16750009. The next prime is 16750061. The reversal of 16750021 is 12005761.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15920100 + 829921 = 3990^2 + 911^2 .

It is an emirp because it is prime and its reverse (12005761) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16750021 - 2⁷ = 16749893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16749974 and 16750001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16750061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8375010 + 8375011.

It is an arithmetic number, because the mean of its divisors is an integer number (8375011).

Almost surely, 2^16750021 is an apocalyptic number.

It is an amenable number.

16750021 is a deficient number, since it is larger than the sum of its proper divisors (1).

16750021 is an equidigital number, since it uses as much as digits as its factorization.

16750021 is an evil number, because the sum of its binary digits is even.

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

The square root of 16750021 is about 4092.6789514938. The cubic root of 16750021 is about 255.8616042728.

Adding to 16750021 its reverse (12005761), we get a palindrome (28755782).

The spelling of 16750021 in words is "sixteen million, seven hundred fifty thousand, twenty-one".