28397772 has 36 divisors (see below), whose sum is σ = 77306320. Its totient is φ = 8737632.

The previous prime is 28397717. The next prime is 28397779. The reversal of 28397772 is 27779382.

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (28397779) 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 11 ways as a sum of consecutive naturals, for example, 29872 + ... + 30807.

Almost surely, 2^28397772 is an apocalyptic number.

It is an amenable number.

28397772 is an abundant number, since it is smaller than the sum of its proper divisors (48908548).

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

28397772 is a wasteful number, since it uses less digits than its factorization.

28397772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60702 (or 60697 counting only the distinct ones).

The product of its digits is 296352, while the sum is 45.

The square root of 28397772 is about 5328.9559953147. The cubic root of 28397772 is about 305.0900817855.

The spelling of 28397772 in words is "twenty-eight million, three hundred ninety-seven thousand, seven hundred seventy-two".