66378636 has 24 divisors (see below), whose sum is σ = 172093040. Its totient is φ = 22126176.

The previous prime is 66378623. The next prime is 66378643. The reversal of 66378636 is 63687366.

66378636 is a `hidden beast` number, since 6 + 6 + 3 + 7 + 8 + 636 = 666.

It is a super-2 number, since 2×66378636² = 8812246634440992, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66378591 and 66378600.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 307201 + ... + 307416.

Almost surely, 2^66378636 is an apocalyptic number.

It is an amenable number.

66378636 is an abundant number, since it is smaller than the sum of its proper divisors (105714404).

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

66378636 is a wasteful number, since it uses less digits than its factorization.

66378636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 614630 (or 614622 counting only the distinct ones).

The product of its digits is 653184, while the sum is 45.

The square root of 66378636 is about 8147.3085126316. The cubic root of 66378636 is about 404.8953364660.

The spelling of 66378636 in words is "sixty-six million, three hundred seventy-eight thousand, six hundred thirty-six".