21144158 has 32 divisors (see below), whose sum is σ = 38937024. Its totient is φ = 8404992.

The previous prime is 21144121. The next prime is 21144173. The reversal of 21144158 is 85144112.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 16766 + ... + 17982.

It is an arithmetic number, because the mean of its divisors is an integer number (1216782).

Almost surely, 2^21144158 is an apocalyptic number.

21144158 is a deficient number, since it is larger than the sum of its proper divisors (17792866).

21144158 is a wasteful number, since it uses less digits than its factorization.

21144158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1316.

The product of its digits is 1280, while the sum is 26.

The square root of 21144158 is about 4598.2777210604. The cubic root of 21144158 is about 276.5222817212.

The spelling of 21144158 in words is "twenty-one million, one hundred forty-four thousand, one hundred fifty-eight".