28638620 has 24 divisors (see below), whose sum is σ = 60298224. Its totient is φ = 11425536.

The previous prime is 28638613. The next prime is 28638641. The reversal of 28638620 is 2683682.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7007 + ... + 10313.

It is an arithmetic number, because the mean of its divisors is an integer number (2512426).

Almost surely, 2^28638620 is an apocalyptic number.

28638620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28638620 is an abundant number, since it is smaller than the sum of its proper divisors (31659604).

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

28638620 is a wasteful number, since it uses less digits than its factorization.

28638620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3749 (or 3747 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 28638620 is about 5351.5063299972. The cubic root of 28638620 is about 305.9501677435.

The spelling of 28638620 in words is "twenty-eight million, six hundred thirty-eight thousand, six hundred twenty".