21084801 has 4 divisors (see below), whose sum is σ = 28113072. Its totient is φ = 14056532.

The previous prime is 21084797. The next prime is 21084803. The reversal of 21084801 is 10848012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21084801 - 2² = 21084797 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21084803) 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, 3514131 + ... + 3514136.

It is an arithmetic number, because the mean of its divisors is an integer number (7028268).

Almost surely, 2^21084801 is an apocalyptic number.

It is an amenable number.

21084801 is a deficient number, since it is larger than the sum of its proper divisors (7028271).

21084801 is an equidigital number, since it uses as much as digits as its factorization.

21084801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7028270.

The product of its (nonzero) digits is 512, while the sum is 24.

The square root of 21084801 is about 4591.8189206457. The cubic root of 21084801 is about 276.2632832143.

The spelling of 21084801 in words is "twenty-one million, eighty-four thousand, eight hundred one".