28723444 has 6 divisors (see below), whose sum is σ = 50266034. Its totient is φ = 14361720.

The previous prime is 28723423. The next prime is 28723447. The reversal of 28723444 is 44432782.

It can be written as a sum of positive squares in only one way, i.e., 21270544 + 7452900 = 4612^2 + 2730^2 .

It is a super-2 number, since 2×28723444² = 1650072470442272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28723447) 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 as a sum of consecutive naturals, namely, 3590427 + ... + 3590434.

Almost surely, 2^28723444 is an apocalyptic number.

It is an amenable number.

28723444 is a deficient number, since it is larger than the sum of its proper divisors (21542590).

28723444 is a wasteful number, since it uses less digits than its factorization.

28723444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7180865 (or 7180863 counting only the distinct ones).

The product of its digits is 43008, while the sum is 34.

The square root of 28723444 is about 5359.4257155035. The cubic root of 28723444 is about 306.2519320161.

The spelling of 28723444 in words is "twenty-eight million, seven hundred twenty-three thousand, four hundred forty-four".