28413640 has 16 divisors (see below), whose sum is σ = 63930780. Its totient is φ = 11365440.

The previous prime is 28413629. The next prime is 28413641. The reversal of 28413640 is 4631482.

It can be written as a sum of positive squares in 2 ways, for example, as 25462116 + 2951524 = 5046^2 + 1718^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28413599 and 28413608.

It is not an unprimeable number, because it can be changed into a prime (28413641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 355131 + ... + 355210.

Almost surely, 2^28413640 is an apocalyptic number.

28413640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28413640 is an abundant number, since it is smaller than the sum of its proper divisors (35517140).

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

28413640 is a wasteful number, since it uses less digits than its factorization.

28413640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 710352 (or 710348 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 28413640 is about 5330.4446343621. Note that the first 3 decimals coincide. The cubic root of 28413640 is about 305.1468968998.

It can be divided in two parts, 284 and 13640, that added together give a square (13924 = 118²).

The spelling of 28413640 in words is "twenty-eight million, four hundred thirteen thousand, six hundred forty".