28034640 has 80 divisors (see below), whose sum is σ = 96571200. Its totient is φ = 7475328.

The previous prime is 28034639. The next prime is 28034647. The reversal of 28034640 is 4643082.

28034640 is a `hidden beast` number, since 280 + 346 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28034647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4330 + ... + 8649.

It is an arithmetic number, because the mean of its divisors is an integer number (1207140).

Almost surely, 2^28034640 is an apocalyptic number.

28034640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28034640 is an abundant number, since it is smaller than the sum of its proper divisors (68536560).

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

28034640 is a wasteful number, since it uses less digits than its factorization.

28034640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13001 (or 12989 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 28034640 is about 5294.7747827457. The cubic root of 28034640 is about 303.7840687286.

The spelling of 28034640 in words is "twenty-eight million, thirty-four thousand, six hundred forty".