66923729 has 2 divisors, whose sum is σ = 66923730. Its totient is φ = 66923728.

The previous prime is 66923707. The next prime is 66923741. The reversal of 66923729 is 92732966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57032704 + 9891025 = 7552^2 + 3145^2 .

It is a cyclic number.

It is not a de Polignac number, because 66923729 - 2⁸ = 66923473 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66923729.

It is not a weakly prime, because it can be changed into another prime (66923749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33461864 + 33461865.

It is an arithmetic number, because the mean of its divisors is an integer number (33461865).

Almost surely, 2^66923729 is an apocalyptic number.

It is an amenable number.

66923729 is a deficient number, since it is larger than the sum of its proper divisors (1).

66923729 is an equidigital number, since it uses as much as digits as its factorization.

66923729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 244944, while the sum is 44.

The square root of 66923729 is about 8180.6924523539. The cubic root of 66923729 is about 406.0006329514. Note that the first 3 decimals are identical.

The spelling of 66923729 in words is "sixty-six million, nine hundred twenty-three thousand, seven hundred twenty-nine".