21142158 has 16 divisors (see below), whose sum is σ = 42499200. Its totient is φ = 7011576.

The previous prime is 21142153. The next prime is 21142171. The reversal of 21142158 is 85124112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21142153) 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 in 7 ways as a sum of consecutive naturals, for example, 7660 + ... + 10047.

It is an arithmetic number, because the mean of its divisors is an integer number (2656200).

Almost surely, 2^21142158 is an apocalyptic number.

21142158 is an abundant number, since it is smaller than the sum of its proper divisors (21357042).

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

21142158 is a wasteful number, since it uses less digits than its factorization.

21142158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17911.

The product of its digits is 640, while the sum is 24.

The square root of 21142158 is about 4598.0602431895. The cubic root of 21142158 is about 276.5135628117.

The spelling of 21142158 in words is "twenty-one million, one hundred forty-two thousand, one hundred fifty-eight".