66994453 has 2 divisors, whose sum is σ = 66994454. Its totient is φ = 66994452.

The previous prime is 66994429. The next prime is 66994481. The reversal of 66994453 is 35449966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34023889 + 32970564 = 5833^2 + 5742^2 .

It is a cyclic number.

It is not a de Polignac number, because 66994453 - 2¹³ = 66986261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66994493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33497226 + 33497227.

It is an arithmetic number, because the mean of its divisors is an integer number (33497227).

Almost surely, 2^66994453 is an apocalyptic number.

It is an amenable number.

66994453 is a deficient number, since it is larger than the sum of its proper divisors (1).

66994453 is an equidigital number, since it uses as much as digits as its factorization.

66994453 is an evil number, because the sum of its binary digits is even.

The product of its digits is 699840, while the sum is 46.

The square root of 66994453 is about 8185.0139279051. The cubic root of 66994453 is about 406.1436010749.

The spelling of 66994453 in words is "sixty-six million, nine hundred ninety-four thousand, four hundred fifty-three".