28722232 has 48 divisors (see below), whose sum is σ = 68352120. Its totient is φ = 11188800.

The previous prime is 28722229. The next prime is 28722241. The reversal of 28722232 is 23222782.

It is a super-2 number, since 2×28722232² = 1649933222123648, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a self number, because there is not a number n which added to its sum of digits gives 28722232.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 982 + ... + 7642.

Almost surely, 2^28722232 is an apocalyptic number.

28722232 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28722232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34176060).

28722232 is an abundant number, since it is smaller than the sum of its proper divisors (39629888).

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

28722232 is a wasteful number, since it uses less digits than its factorization.

28722232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6692 (or 6681 counting only the distinct ones).

The product of its digits is 5376, while the sum is 28.

The square root of 28722232 is about 5359.3126424944. The cubic root of 28722232 is about 306.2476244714.

The spelling of 28722232 in words is "twenty-eight million, seven hundred twenty-two thousand, two hundred thirty-two".