16875821 has 2 divisors, whose sum is σ = 16875822. Its totient is φ = 16875820.

The previous prime is 16875799. The next prime is 16875839. The reversal of 16875821 is 12857861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9853321 + 7022500 = 3139^2 + 2650^2 .

It is a cyclic number.

It is not a de Polignac number, because 16875821 - 2⁶ = 16875757 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16875841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8437910 + 8437911.

It is an arithmetic number, because the mean of its divisors is an integer number (8437911).

Almost surely, 2^16875821 is an apocalyptic number.

It is an amenable number.

16875821 is a deficient number, since it is larger than the sum of its proper divisors (1).

16875821 is an equidigital number, since it uses as much as digits as its factorization.

16875821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26880, while the sum is 38.

The square root of 16875821 is about 4108.0191090111. The cubic root of 16875821 is about 256.5005516089.

The spelling of 16875821 in words is "sixteen million, eight hundred seventy-five thousand, eight hundred twenty-one".