72808706 has 4 divisors (see below), whose sum is σ = 109213062. Its totient is φ = 36404352.

The previous prime is 72808693. The next prime is 72808709. The reversal of 72808706 is 60780827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60780827 = 61 ⋅996407.

It can be written as a sum of positive squares in only one way, i.e., 64657681 + 8151025 = 8041^2 + 2855^2 .

It is a super-2 number, since 2×72808706² = 10602215338788872, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 72808706.

It is not an unprimeable number, because it can be changed into a prime (72808709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18202175 + ... + 18202178.

Almost surely, 2^72808706 is an apocalyptic number.

72808706 is a deficient number, since it is larger than the sum of its proper divisors (36404356).

72808706 is a wasteful number, since it uses less digits than its factorization.

72808706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36404355.

The product of its (nonzero) digits is 37632, while the sum is 38.

The square root of 72808706 is about 8532.8017672978. The cubic root of 72808706 is about 417.5685397890.

The spelling of 72808706 in words is "seventy-two million, eight hundred eight thousand, seven hundred six".