66723864 has 16 divisors (see below), whose sum is σ = 166809720. Its totient is φ = 22241280.

The previous prime is 66723863. The next prime is 66723871. The reversal of 66723864 is 46832766.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66723863) 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 3 ways as a sum of consecutive naturals, for example, 1390057 + ... + 1390104.

Almost surely, 2^66723864 is an apocalyptic number.

It is an amenable number.

66723864 is an abundant number, since it is smaller than the sum of its proper divisors (100085856).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66723864 is a wasteful number, since it uses less digits than its factorization.

66723864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2780170 (or 2780166 counting only the distinct ones).

The product of its digits is 290304, while the sum is 42.

The square root of 66723864 is about 8168.4676653581. The cubic root of 66723864 is about 405.5960618021.

It can be divided in two parts, 667 and 23864, that added together give a triangular number (24531 = T₂₂₁).

The spelling of 66723864 in words is "sixty-six million, seven hundred twenty-three thousand, eight hundred sixty-four".