21401330 has 16 divisors (see below), whose sum is σ = 38617344. Its totient is φ = 8539440.

The previous prime is 21401327. The next prime is 21401363. The reversal of 21401330 is 3310412.

It is an unprimeable number.

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, 2015 + ... + 6845.

It is an arithmetic number, because the mean of its divisors is an integer number (2413584).

Almost surely, 2^21401330 is an apocalyptic number.

21401330 is a deficient number, since it is larger than the sum of its proper divisors (17216014).

21401330 is a wasteful number, since it uses less digits than its factorization.

21401330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5281.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21401330 is about 4626.1571525403. The cubic root of 21401330 is about 277.6388613248.

Adding to 21401330 its reverse (3310412), we get a palindrome (24711742).

The spelling of 21401330 in words is "twenty-one million, four hundred one thousand, three hundred thirty".