21270284 has 12 divisors (see below), whose sum is σ = 42540624. Its totient is φ = 9115824.

The previous prime is 21270269. The next prime is 21270299. The reversal of 21270284 is 48207212.

It is an interprime number because it is at equal distance from previous prime (21270269) and next prime (21270299).

21270284 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 379799 + ... + 379854.

It is an arithmetic number, because the mean of its divisors is an integer number (3545052).

Almost surely, 2^21270284 is an apocalyptic number.

It is an amenable number.

21270284 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21270284 is a wasteful number, since it uses less digits than its factorization.

21270284 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 759664 (or 759662 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 21270284 is about 4611.9718125765. The cubic root of 21270284 is about 277.0710153430.

Adding to 21270284 its reverse (48207212), we get a palindrome (69477496).

The spelling of 21270284 in words is "twenty-one million, two hundred seventy thousand, two hundred eighty-four".