21041370 has 96 divisors (see below), whose sum is σ = 64891008. Its totient is φ = 4805568.

The previous prime is 21041369. The next prime is 21041381. The reversal of 21041370 is 7314012.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 16392 + ... + 17628.

It is an arithmetic number, because the mean of its divisors is an integer number (675948).

Almost surely, 2^21041370 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21041370, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32445504).

21041370 is an abundant number, since it is smaller than the sum of its proper divisors (43849638).

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

21041370 is a wasteful number, since it uses less digits than its factorization.

21041370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1266 (or 1254 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 21041370 is about 4587.0873111376. The cubic root of 21041370 is about 276.0734681545.

Adding to 21041370 its reverse (7314012), we get a palindrome (28355382).

The spelling of 21041370 in words is "twenty-one million, forty-one thousand, three hundred seventy".