66823856 has 20 divisors (see below), whose sum is σ = 141241704. Its totient is φ = 30374400.

The previous prime is 66823837. The next prime is 66823871. The reversal of 66823856 is 65832866.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 189665 + ... + 190016.

Almost surely, 2^66823856 is an apocalyptic number.

66823856 is the 4370-th centered heptagonal number.

It is an amenable number.

66823856 is an abundant number, since it is smaller than the sum of its proper divisors (74417848).

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

66823856 is a wasteful number, since it uses less digits than its factorization.

66823856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379700 (or 379694 counting only the distinct ones).

The product of its digits is 414720, while the sum is 44.

The square root of 66823856 is about 8174.5859834000. The cubic root of 66823856 is about 405.7985686548.

The spelling of 66823856 in words is "sixty-six million, eight hundred twenty-three thousand, eight hundred fifty-six".