72728287 has 4 divisors (see below), whose sum is σ = 73920616. Its totient is φ = 71535960.

The previous prime is 72728239. The next prime is 72728309. The reversal of 72728287 is 78282727.

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

It is a cyclic number.

It is not a de Polignac number, because 72728287 - 2¹¹ = 72726239 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72728207) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 596073 + ... + 596194.

It is an arithmetic number, because the mean of its divisors is an integer number (18480154).

Almost surely, 2^72728287 is an apocalyptic number.

72728287 is a deficient number, since it is larger than the sum of its proper divisors (1192329).

72728287 is a wasteful number, since it uses less digits than its factorization.

72728287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1192328.

The product of its digits is 175616, while the sum is 43.

The square root of 72728287 is about 8528.0881210269. The cubic root of 72728287 is about 417.4147449234.

The spelling of 72728287 in words is "seventy-two million, seven hundred twenty-eight thousand, two hundred eighty-seven".