21100327 has 4 divisors (see below), whose sum is σ = 21446296. Its totient is φ = 20754360.

The previous prime is 21100319. The next prime is 21100351. The reversal of 21100327 is 72300112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21100327 - 2³ = 21100319 is a prime.

It is a super-4 number, since 4×21100327⁴ (a number of 30 digits) contains 4444 as substring. Note that it is a super-d number also for d = 3.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21100327.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100357) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172893 + ... + 173014.

It is an arithmetic number, because the mean of its divisors is an integer number (5361574).

Almost surely, 2^21100327 is an apocalyptic number.

21100327 is a deficient number, since it is larger than the sum of its proper divisors (345969).

21100327 is an equidigital number, since it uses as much as digits as its factorization.

21100327 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345968.

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 21100327 is about 4593.5092249826. The cubic root of 21100327 is about 276.3310763030.

Adding to 21100327 its reverse (72300112), we get a palindrome (93400439).

The spelling of 21100327 in words is "twenty-one million, one hundred thousand, three hundred twenty-seven".