28647620 has 24 divisors (see below), whose sum is σ = 61787544. Its totient is φ = 11149056.

The previous prime is 28647599. The next prime is 28647623. The reversal of 28647620 is 2674682.

It can be written as a sum of positive squares in 4 ways, for example, as 12503296 + 16144324 = 3536^2 + 4018^2 .

It is a super-2 number, since 2×28647620² = 1641372263328800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28647623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18617 + ... + 20096.

It is an arithmetic number, because the mean of its divisors is an integer number (2574481).

Almost surely, 2^28647620 is an apocalyptic number.

28647620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28647620 is an abundant number, since it is smaller than the sum of its proper divisors (33139924).

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

28647620 is a wasteful number, since it uses less digits than its factorization.

28647620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38759 (or 38757 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 35.

The square root of 28647620 is about 5352.3471486816. The cubic root of 28647620 is about 305.9822137839.

The spelling of 28647620 in words is "twenty-eight million, six hundred forty-seven thousand, six hundred twenty".