28778232 has 32 divisors (see below), whose sum is σ = 82224000. Its totient is φ = 8222304.

The previous prime is 28778231. The next prime is 28778273. The reversal of 28778232 is 23287782.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28778231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85482 + ... + 85817.

It is an arithmetic number, because the mean of its divisors is an integer number (2569500).

Almost surely, 2^28778232 is an apocalyptic number.

It is an amenable number.

28778232 is an abundant number, since it is smaller than the sum of its proper divisors (53445768).

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

28778232 is a wasteful number, since it uses less digits than its factorization.

28778232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171315 (or 171311 counting only the distinct ones).

The product of its digits is 75264, while the sum is 39.

The square root of 28778232 is about 5364.5346489700. The cubic root of 28778232 is about 306.4465265307.

The spelling of 28778232 in words is "twenty-eight million, seven hundred seventy-eight thousand, two hundred thirty-two".