66866431 has 8 divisors (see below), whose sum is σ = 70308000. Its totient is φ = 63500640.

The previous prime is 66866417. The next prime is 66866483. The reversal of 66866431 is 13466866.

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 66866431 - 2⁵ = 66866399 is a prime.

It is a super-2 number, since 2×66866431² = 8942239189355522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66866131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17131 + ... + 20668.

It is an arithmetic number, because the mean of its divisors is an integer number (8788500).

Almost surely, 2^66866431 is an apocalyptic number.

66866431 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

66866431 is a deficient number, since it is larger than the sum of its proper divisors (3441569).

66866431 is a wasteful number, since it uses less digits than its factorization.

66866431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37889.

The product of its digits is 124416, while the sum is 40.

The square root of 66866431 is about 8177.1896761663. The cubic root of 66866431 is about 405.8847315275.

The spelling of 66866431 in words is "sixty-six million, eight hundred sixty-six thousand, four hundred thirty-one".