22728739 has 4 divisors (see below), whose sum is σ = 24795000. Its totient is φ = 20662480.

The previous prime is 22728703. The next prime is 22728757. The reversal of 22728739 is 93782722.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22728739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22728799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1033114 + ... + 1033135.

It is an arithmetic number, because the mean of its divisors is an integer number (6198750).

Almost surely, 2^22728739 is an apocalyptic number.

22728739 is a deficient number, since it is larger than the sum of its proper divisors (2066261).

22728739 is a wasteful number, since it uses less digits than its factorization.

22728739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2066260.

The product of its digits is 84672, while the sum is 40.

The square root of 22728739 is about 4767.4667277287. The cubic root of 22728739 is about 283.2642589017.

It can be divided in two parts, 2272 and 8739, that added together give a palindrome (11011).

The spelling of 22728739 in words is "twenty-two million, seven hundred twenty-eight thousand, seven hundred thirty-nine".