28764540 has 144 divisors (see below), whose sum is σ = 102578112. Its totient is φ = 6386688.

The previous prime is 28764529. The next prime is 28764551. The reversal of 28764540 is 4546782.

28764540 is a `hidden beast` number, since 2 + 8 + 7 + 645 + 4 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (28764529) and next prime (28764551).

It is a super-2 number, since 2×28764540² = 1654797522823200, which contains 22 as substring.

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 = 28764495 and 28764504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 46312 + ... + 46928.

It is an arithmetic number, because the mean of its divisors is an integer number (712348).

Almost surely, 2^28764540 is an apocalyptic number.

28764540 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 28764540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51289056).

28764540 is an abundant number, since it is smaller than the sum of its proper divisors (73813572).

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

28764540 is a wasteful number, since it uses less digits than its factorization.

28764540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 676 (or 671 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

The square root of 28764540 is about 5363.2583379882. The cubic root of 28764540 is about 306.3979188255.

The spelling of 28764540 in words is "twenty-eight million, seven hundred sixty-four thousand, five hundred forty".