21159158 has 4 divisors (see below), whose sum is σ = 31738740. Its totient is φ = 10579578.

The previous prime is 21159133. The next prime is 21159161. The reversal of 21159158 is 85195112.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5289788 + ... + 5289791.

It is an arithmetic number, because the mean of its divisors is an integer number (7934685).

Almost surely, 2^21159158 is an apocalyptic number.

21159158 is a deficient number, since it is larger than the sum of its proper divisors (10579582).

21159158 is a wasteful number, since it uses less digits than its factorization.

21159158 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10579581.

The product of its digits is 3600, while the sum is 32.

The square root of 21159158 is about 4599.9084773504. The cubic root of 21159158 is about 276.5876560241.

The spelling of 21159158 in words is "twenty-one million, one hundred fifty-nine thousand, one hundred fifty-eight".