21082788 has 48 divisors (see below), whose sum is σ = 57879360. Its totient is φ = 6613632.

The previous prime is 21082783. The next prime is 21082801. The reversal of 21082788 is 88728012.

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

It is not an unprimeable number, because it can be changed into a prime (21082783) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3906 + ... + 7577.

It is an arithmetic number, because the mean of its divisors is an integer number (1205820).

Almost surely, 2^21082788 is an apocalyptic number.

It is an amenable number.

21082788 is an abundant number, since it is smaller than the sum of its proper divisors (36796572).

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

21082788 is a wasteful number, since it uses less digits than its factorization.

21082788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11513 (or 11505 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 36.

The square root of 21082788 is about 4591.5997212301. The cubic root of 21082788 is about 276.2544911673.

The spelling of 21082788 in words is "twenty-one million, eighty-two thousand, seven hundred eighty-eight".