28913724 has 108 divisors (see below), whose sum is σ = 87515064. Its totient is φ = 8019648.

The previous prime is 28913723. The next prime is 28913741. The reversal of 28913724 is 42731982.

28913724 is a `hidden beast` number, since 289 + 1 + 372 + 4 = 666.

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

Its product of digits (24192) is a multiple of the sum of its prime factors (504).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28913723) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 65047 + ... + 65489.

Almost surely, 2^28913724 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28913724, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43757532).

28913724 is an abundant number, since it is smaller than the sum of its proper divisors (58601340).

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

28913724 is a wasteful number, since it uses less digits than its factorization.

28913724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504 (or 492 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 28913724 is about 5377.1483148598. The cubic root of 28913724 is about 306.9267049788.

The spelling of 28913724 in words is "twenty-eight million, nine hundred thirteen thousand, seven hundred twenty-four".