21143254 has 16 divisors (see below), whose sum is σ = 35017920. Its totient is φ = 9493960.

The previous prime is 21143251. The next prime is 21143261. The reversal of 21143254 is 45234112.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21143251) by changing a digit.

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, 3964 + ... + 7615.

It is an arithmetic number, because the mean of its divisors is an integer number (2188620).

Almost surely, 2^21143254 is an apocalyptic number.

21143254 is a deficient number, since it is larger than the sum of its proper divisors (13874666).

21143254 is a wasteful number, since it uses less digits than its factorization.

21143254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11675.

The product of its digits is 960, while the sum is 22.

The square root of 21143254 is about 4598.1794223366. The cubic root of 21143254 is about 276.5183408422.

Adding to 21143254 its reverse (45234112), we get a palindrome (66377366).

The spelling of 21143254 in words is "twenty-one million, one hundred forty-three thousand, two hundred fifty-four".