66786845 has 4 divisors (see below), whose sum is σ = 80144220. Its totient is φ = 53429472.

The previous prime is 66786799. The next prime is 66786851. The reversal of 66786845 is 54868766.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54868766 = 2 ⋅27434383.

It can be written as a sum of positive squares in 2 ways, for example, as 47803396 + 18983449 = 6914^2 + 4357^2 .

It is a cyclic number.

It is not a de Polignac number, because 66786845 - 2⁶ = 66786781 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 66786793 and 66786802.

It is a congruent number.

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, 6678680 + ... + 6678689.

It is an arithmetic number, because the mean of its divisors is an integer number (20036055).

Almost surely, 2^66786845 is an apocalyptic number.

It is an amenable number.

66786845 is a deficient number, since it is larger than the sum of its proper divisors (13357375).

66786845 is a wasteful number, since it uses less digits than its factorization.

66786845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13357374.

The product of its digits is 1935360, while the sum is 50.

The square root of 66786845 is about 8172.3218854864. The cubic root of 66786845 is about 405.7236364106.

The spelling of 66786845 in words is "sixty-six million, seven hundred eighty-six thousand, eight hundred forty-five".