66996291 has 8 divisors (see below), whose sum is σ = 91229184. Its totient is φ = 43713800.

The previous prime is 66996277. The next prime is 66996311. The reversal of 66996291 is 19269966.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66996291 - 2¹⁸ = 66734147 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66996291.

It is not an unprimeable number, because it can be changed into a prime (66996491) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 237435 + ... + 237716.

It is an arithmetic number, because the mean of its divisors is an integer number (11403648).

Almost surely, 2^66996291 is an apocalyptic number.

66996291 is a deficient number, since it is larger than the sum of its proper divisors (24232893).

66996291 is a wasteful number, since it uses less digits than its factorization.

66996291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475201.

The product of its digits is 314928, while the sum is 48.

The square root of 66996291 is about 8185.1262055023. The cubic root of 66996291 is about 406.1473152387.

It can be divided in two parts, 6699629 and 1, that added together give a triangular number (6699630 = T₃₆₆₀).

The spelling of 66996291 in words is "sixty-six million, nine hundred ninety-six thousand, two hundred ninety-one".