28634940 has 72 divisors (see below), whose sum is σ = 87338160. Its totient is φ = 7593984.

The previous prime is 28634923. The next prime is 28634951. The reversal of 28634940 is 4943682.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 28634895 and 28634904.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 45951 + ... + 46569.

It is an arithmetic number, because the mean of its divisors is an integer number (1213030).

Almost surely, 2^28634940 is an apocalyptic number.

28634940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28634940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43669080).

28634940 is an abundant number, since it is smaller than the sum of its proper divisors (58703220).

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

28634940 is a wasteful number, since it uses less digits than its factorization.

28634940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 891 (or 886 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 28634940 is about 5351.1624905248. The cubic root of 28634940 is about 305.9370625398.

The spelling of 28634940 in words is "twenty-eight million, six hundred thirty-four thousand, nine hundred forty".