66402769 has 2 divisors, whose sum is σ = 66402770. Its totient is φ = 66402768.

The previous prime is 66402767. The next prime is 66402773. The reversal of 66402769 is 96720466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60217600 + 6185169 = 7760^2 + 2487^2 .

It is a cyclic number.

It is not a de Polignac number, because 66402769 - 2¹ = 66402767 is a prime.

It is a super-2 number, since 2×66402769² = 8818655461734722, which contains 22 as substring.

Together with 66402767, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66402767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33201384 + 33201385.

It is an arithmetic number, because the mean of its divisors is an integer number (33201385).

Almost surely, 2^66402769 is an apocalyptic number.

It is an amenable number.

66402769 is a deficient number, since it is larger than the sum of its proper divisors (1).

66402769 is an equidigital number, since it uses as much as digits as its factorization.

66402769 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 40.

The square root of 66402769 is about 8148.7894192941. The cubic root of 66402769 is about 404.9443992157.

It can be divided in two parts, 6640 and 2769, that added together give a square (9409 = 97²).

The spelling of 66402769 in words is "sixty-six million, four hundred two thousand, seven hundred sixty-nine".