21270774 has 64 divisors (see below), whose sum is σ = 53194752. Its totient is φ = 5535360.

The previous prime is 21270773. The next prime is 21270779. The reversal of 21270774 is 47707212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21270773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 686139 + ... + 686169.

It is an arithmetic number, because the mean of its divisors is an integer number (831168).

Almost surely, 2^21270774 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21270774, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26597376).

21270774 is an abundant number, since it is smaller than the sum of its proper divisors (31923978).

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

21270774 is an equidigital number, since it uses as much as digits as its factorization.

21270774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 5488, while the sum is 30.

The square root of 21270774 is about 4612.0249348849. The cubic root of 21270774 is about 277.0731429397.

Adding to 21270774 its reverse (47707212), we get a palindrome (68977986).

The spelling of 21270774 in words is "twenty-one million, two hundred seventy thousand, seven hundred seventy-four".