21041420 has 24 divisors (see below), whose sum is σ = 44307648. Its totient is φ = 8393600.

The previous prime is 21041411. The next prime is 21041429. The reversal of 21041420 is 2414012.

It is an interprime number because it is at equal distance from previous prime (21041411) and next prime (21041429).

It is a junction number, because it is equal to n+sod(n) for n = 21041395 and 21041404.

It is not an unprimeable number, because it can be changed into a prime (21041429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7400 + ... + 9840.

It is an arithmetic number, because the mean of its divisors is an integer number (1846152).

Almost surely, 2^21041420 is an apocalyptic number.

21041420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21041420 is an abundant number, since it is smaller than the sum of its proper divisors (23266228).

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

21041420 is a wasteful number, since it uses less digits than its factorization.

21041420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2881 (or 2879 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 21041420 is about 4587.0927612160. The cubic root of 21041420 is about 276.0736868295.

Adding to 21041420 its reverse (2414012), we get a palindrome (23455432).

The spelling of 21041420 in words is "twenty-one million, forty-one thousand, four hundred twenty".