28438726 has 4 divisors (see below), whose sum is σ = 42658092. Its totient is φ = 14219362.

The previous prime is 28438703. The next prime is 28438733. The reversal of 28438726 is 62783482.

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

It is a super-2 number, since 2×28438726² = 1617522273006152, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 7109680 + ... + 7109683.

It is an arithmetic number, because the mean of its divisors is an integer number (10664523).

Almost surely, 2^28438726 is an apocalyptic number.

28438726 is the 2851-st centered heptagonal number.

28438726 is a deficient number, since it is larger than the sum of its proper divisors (14219366).

28438726 is a wasteful number, since it uses less digits than its factorization.

28438726 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14219365.

The product of its digits is 129024, while the sum is 40.

The square root of 28438726 is about 5332.7972022195. The cubic root of 28438726 is about 305.2366737741.

The spelling of 28438726 in words is "twenty-eight million, four hundred thirty-eight thousand, seven hundred twenty-six".