66699293 has 2 divisors, whose sum is σ = 66699294. Its totient is φ = 66699292.

The previous prime is 66699263. The next prime is 66699307. The reversal of 66699293 is 39299666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65885689 + 813604 = 8117^2 + 902^2 .

It is a cyclic number.

It is not a de Polignac number, because 66699293 - 2⁶ = 66699229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66699223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33349646 + 33349647.

It is an arithmetic number, because the mean of its divisors is an integer number (33349647).

Almost surely, 2^66699293 is an apocalyptic number.

It is an amenable number.

66699293 is a deficient number, since it is larger than the sum of its proper divisors (1).

66699293 is an equidigital number, since it uses as much as digits as its factorization.

66699293 is an evil number, because the sum of its binary digits is even.

The product of its digits is 944784, while the sum is 50.

The square root of 66699293 is about 8166.9635116119. The cubic root of 66699293 is about 405.5462689004.

The spelling of 66699293 in words is "sixty-six million, six hundred ninety-nine thousand, two hundred ninety-three".