21877530 has 32 divisors (see below), whose sum is σ = 52899264. Its totient is φ = 5790336.

The previous prime is 21877529. The next prime is 21877561. The reversal of 21877530 is 3577812.

It is a junction number, because it is equal to n+sod(n) for n = 21877491 and 21877500.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1449 + ... + 6771.

It is an arithmetic number, because the mean of its divisors is an integer number (1653102).

Almost surely, 2^21877530 is an apocalyptic number.

21877530 is an abundant number, since it is smaller than the sum of its proper divisors (31021734).

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

21877530 is a wasteful number, since it uses less digits than its factorization.

21877530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5470.

The product of its (nonzero) digits is 11760, while the sum is 33.

The square root of 21877530 is about 4677.3421940243. The cubic root of 21877530 is about 279.6830171353.

The spelling of 21877530 in words is "twenty-one million, eight hundred seventy-seven thousand, five hundred thirty".