72028399 has 4 divisors (see below), whose sum is σ = 72689320. Its totient is φ = 71367480.

The previous prime is 72028379. The next prime is 72028403. The reversal of 72028399 is 99382027.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99382027 = 19 ⋅5230633.

It is a cyclic number.

It is not a de Polignac number, because 72028399 - 2⁵ = 72028367 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 (72028309) 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, 330297 + ... + 330514.

It is an arithmetic number, because the mean of its divisors is an integer number (18172330).

Almost surely, 2^72028399 is an apocalyptic number.

72028399 is a deficient number, since it is larger than the sum of its proper divisors (660921).

72028399 is a wasteful number, since it uses less digits than its factorization.

72028399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660920.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 72028399 is about 8486.9546363817. The cubic root of 72028399 is about 416.0714539952.

It can be divided in two parts, 72028 and 399, that added together give a palindrome (72427).

The spelling of 72028399 in words is "seventy-two million, twenty-eight thousand, three hundred ninety-nine".