28137744 has 30 divisors (see below), whose sum is σ = 78747006. Its totient is φ = 9379200.

The previous prime is 28137731. The next prime is 28137751. The reversal of 28137744 is 44773182.

It is a happy number.

28137744 is a `hidden beast` number, since 281 + 377 + 4 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 25887744 + 2250000 = 5088^2 + 1500^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 28137699 and 28137708.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 97557 + ... + 97844.

Almost surely, 2^28137744 is an apocalyptic number.

28137744 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

28137744 is an abundant number, since it is smaller than the sum of its proper divisors (50609262).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28137744 is a wasteful number, since it uses less digits than its factorization.

28137744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195415 (or 195406 counting only the distinct ones).

The product of its digits is 37632, while the sum is 36.

The square root of 28137744 is about 5304.5022386648. The cubic root of 28137744 is about 304.1560256322.

It can be divided in two parts, 281 and 37744, that added together give a square (38025 = 195²).

The spelling of 28137744 in words is "twenty-eight million, one hundred thirty-seven thousand, seven hundred forty-four".