28751640 has 32 divisors (see below), whose sum is σ = 86255280. Its totient is φ = 7667072.

The previous prime is 28751629. The next prime is 28751647. The reversal of 28751640 is 4615782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28751647) 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, 119679 + ... + 119918.

Almost surely, 2^28751640 is an apocalyptic number.

28751640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28751640 is an abundant number, since it is smaller than the sum of its proper divisors (57503640).

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

28751640 is a wasteful number, since it uses less digits than its factorization.

28751640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239611 (or 239607 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 33.

The square root of 28751640 is about 5362.0555759895. The cubic root of 28751640 is about 306.3521086699.

The spelling of 28751640 in words is "twenty-eight million, seven hundred fifty-one thousand, six hundred forty".