66326921 has 2 divisors, whose sum is σ = 66326922. Its totient is φ = 66326920.

The previous prime is 66326879. The next prime is 66326927. The reversal of 66326921 is 12962366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58736896 + 7590025 = 7664^2 + 2755^2 .

It is a cyclic number.

It is not a de Polignac number, because 66326921 - 2¹⁴ = 66310537 is a prime.

It is not a weakly prime, because it can be changed into another prime (66326927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33163460 + 33163461.

It is an arithmetic number, because the mean of its divisors is an integer number (33163461).

Almost surely, 2^66326921 is an apocalyptic number.

It is an amenable number.

66326921 is a deficient number, since it is larger than the sum of its proper divisors (1).

66326921 is an equidigital number, since it uses as much as digits as its factorization.

66326921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23328, while the sum is 35.

The square root of 66326921 is about 8144.1341467341. The cubic root of 66326921 is about 404.7901590385.

The spelling of 66326921 in words is "sixty-six million, three hundred twenty-six thousand, nine hundred twenty-one".