66469891 has 8 divisors (see below), whose sum is σ = 68016960. Its totient is φ = 64928448.

The previous prime is 66469861. The next prime is 66469901. The reversal of 66469891 is 19896466.

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 66469891 - 2⁷ = 66469763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66469811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30775 + ... + 32863.

It is an arithmetic number, because the mean of its divisors is an integer number (8502120).

Almost surely, 2^66469891 is an apocalyptic number.

66469891 is a deficient number, since it is larger than the sum of its proper divisors (1547069).

66469891 is a wasteful number, since it uses less digits than its factorization.

66469891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2813.

The product of its digits is 559872, while the sum is 49.

The square root of 66469891 is about 8152.9069049021. The cubic root of 66469891 is about 405.0807967643.

The spelling of 66469891 in words is "sixty-six million, four hundred sixty-nine thousand, eight hundred ninety-one".