72866777 has 4 divisors (see below), whose sum is σ = 77153076. Its totient is φ = 68580480.

The previous prime is 72866747. The next prime is 72866791. The reversal of 72866777 is 77766827.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 56310016 + 16556761 = 7504^2 + 4069^2 .

It is a cyclic number.

It is not a de Polignac number, because 72866777 - 2¹² = 72862681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72866707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2143124 + ... + 2143157.

It is an arithmetic number, because the mean of its divisors is an integer number (19288269).

Almost surely, 2^72866777 is an apocalyptic number.

It is an amenable number.

72866777 is a deficient number, since it is larger than the sum of its proper divisors (4286299).

72866777 is a wasteful number, since it uses less digits than its factorization.

72866777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4286298.

The product of its digits is 1382976, while the sum is 50.

The square root of 72866777 is about 8536.2038986894. The cubic root of 72866777 is about 417.6795255035.

Adding to 72866777 its sum of digits (50), we get a palindrome (72866827).

The spelling of 72866777 in words is "seventy-two million, eight hundred sixty-six thousand, seven hundred seventy-seven".