28418640 has 40 divisors (see below), whose sum is σ = 88098528. Its totient is φ = 7578240.

The previous prime is 28418633. The next prime is 28418641. The reversal of 28418640 is 4681482.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-3 number, since 3×28418640³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28418641) 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, 58966 + ... + 59445.

Almost surely, 2^28418640 is an apocalyptic number.

28418640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28418640 is an abundant number, since it is smaller than the sum of its proper divisors (59679888).

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

28418640 is a wasteful number, since it uses less digits than its factorization.

28418640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118427 (or 118421 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 33.

The square root of 28418640 is about 5330.9136177582. The cubic root of 28418640 is about 305.1647949352.

The spelling of 28418640 in words is "twenty-eight million, four hundred eighteen thousand, six hundred forty".