72864817 has 4 divisors (see below), whose sum is σ = 72890980. Its totient is φ = 72838656.

The previous prime is 72864809. The next prime is 72864821. The reversal of 72864817 is 71846827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71846827 = 13 ⋅5526679.

It can be written as a sum of positive squares in 2 ways, for example, as 59969536 + 12895281 = 7744^2 + 3591^2 .

It is a cyclic number.

It is not a de Polignac number, because 72864817 - 2³ = 72864809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72864917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8328 + ... + 14665.

It is an arithmetic number, because the mean of its divisors is an integer number (18222745).

Almost surely, 2^72864817 is an apocalyptic number.

It is an amenable number.

72864817 is a deficient number, since it is larger than the sum of its proper divisors (26163).

72864817 is a wasteful number, since it uses less digits than its factorization.

72864817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26162.

The product of its digits is 150528, while the sum is 43.

The square root of 72864817 is about 8536.0890927872. The cubic root of 72864817 is about 417.6757804991.

The spelling of 72864817 in words is "seventy-two million, eight hundred sixty-four thousand, eight hundred seventeen".