21144374 has 4 divisors (see below), whose sum is σ = 31716564. Its totient is φ = 10572186.

The previous prime is 21144373. The next prime is 21144419. The reversal of 21144374 is 47344112.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144373) 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 as a sum of consecutive naturals, namely, 5286092 + ... + 5286095.

It is an arithmetic number, because the mean of its divisors is an integer number (7929141).

Almost surely, 2^21144374 is an apocalyptic number.

21144374 is a deficient number, since it is larger than the sum of its proper divisors (10572190).

21144374 is a wasteful number, since it uses less digits than its factorization.

21144374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10572189.

The product of its digits is 2688, while the sum is 26.

The square root of 21144374 is about 4598.3012080550. The cubic root of 21144374 is about 276.5232233305.

Adding to 21144374 its reverse (47344112), we get a palindrome (68488486).

The spelling of 21144374 in words is "twenty-one million, one hundred forty-four thousand, three hundred seventy-four".