20814421 has 4 divisors (see below), whose sum is σ = 21125152. Its totient is φ = 20503692.

The previous prime is 20814403. The next prime is 20814439. The reversal of 20814421 is 12441802.

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 an interprime number because it is at equal distance from previous prime (20814403) and next prime (20814439).

It is a cyclic number.

It is not a de Polignac number, because 20814421 - 2¹⁵ = 20781653 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 20814392 and 20814401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20811421) 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, 155265 + ... + 155398.

It is an arithmetic number, because the mean of its divisors is an integer number (5281288).

Almost surely, 2^20814421 is an apocalyptic number.

It is an amenable number.

20814421 is a deficient number, since it is larger than the sum of its proper divisors (310731).

20814421 is an equidigital number, since it uses as much as digits as its factorization.

20814421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310730.

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 20814421 is about 4562.2824331687. The cubic root of 20814421 is about 275.0773160017.

The spelling of 20814421 in words is "twenty million, eight hundred fourteen thousand, four hundred twenty-one".