28515740 has 48 divisors (see below), whose sum is σ = 65729664. Its totient is φ = 10305600.

The previous prime is 28515737. The next prime is 28515779. The reversal of 28515740 is 4751582.

It is a junction number, because it is equal to n+sod(n) for n = 28515697 and 28515706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49655 + ... + 50225.

It is an arithmetic number, because the mean of its divisors is an integer number (1369368).

Almost surely, 2^28515740 is an apocalyptic number.

28515740 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 28515740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32864832).

28515740 is an abundant number, since it is smaller than the sum of its proper divisors (37213924).

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

28515740 is a wasteful number, since it uses less digits than its factorization.

28515740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 818 (or 816 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 32.

The square root of 28515740 is about 5340.0131085981. The cubic root of 28515740 is about 305.5119593019.

The spelling of 28515740 in words is "twenty-eight million, five hundred fifteen thousand, seven hundred forty".