21829275 has 72 divisors (see below), whose sum is σ = 44684640. Its totient is φ = 10091520.

The previous prime is 21829273. The next prime is 21829279. The reversal of 21829275 is 57292812.

It is not a de Polignac number, because 21829275 - 2¹ = 21829273 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21829273) by changing a digit.

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 71 ways as a sum of consecutive naturals, for example, 49506 + ... + 49944.

It is an arithmetic number, because the mean of its divisors is an integer number (620620).

Almost surely, 2^21829275 is an apocalyptic number.

21829275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21829275 is an abundant number, since it is smaller than the sum of its proper divisors (22855365).

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

21829275 is a wasteful number, since it uses less digits than its factorization.

21829275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485 (or 477 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 21829275 is about 4672.1809682417. The cubic root of 21829275 is about 279.4772346284.

The spelling of 21829275 in words is "twenty-one million, eight hundred twenty-nine thousand, two hundred seventy-five".