21274421 has 8 divisors (see below), whose sum is σ = 24712704. Its totient is φ = 17935920.

The previous prime is 21274399. The next prime is 21274427. The reversal of 21274421 is 12447212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21274421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21274427) 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 7 ways as a sum of consecutive naturals, for example, 24485 + ... + 25338.

It is an arithmetic number, because the mean of its divisors is an integer number (3089088).

Almost surely, 2^21274421 is an apocalyptic number.

It is an amenable number.

21274421 is a deficient number, since it is larger than the sum of its proper divisors (3438283).

21274421 is an equidigital number, since it uses as much as digits as its factorization.

21274421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49891.

The product of its digits is 896, while the sum is 23.

The square root of 21274421 is about 4612.4202974144. The cubic root of 21274421 is about 277.0889773111.

The spelling of 21274421 in words is "twenty-one million, two hundred seventy-four thousand, four hundred twenty-one".