21158512 has 20 divisors (see below), whose sum is σ = 41110216. Its totient is φ = 10549440.

The previous prime is 21158471. The next prime is 21158519. The reversal of 21158512 is 21585112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21158519) 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 3 ways as a sum of consecutive naturals, for example, 4687 + ... + 8017.

Almost surely, 2^21158512 is an apocalyptic number.

It is an amenable number.

21158512 is a deficient number, since it is larger than the sum of its proper divisors (19951704).

21158512 is a wasteful number, since it uses less digits than its factorization.

21158512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3736 (or 3730 counting only the distinct ones).

The product of its digits is 800, while the sum is 25.

The square root of 21158512 is about 4599.8382580260. The cubic root of 21158512 is about 276.5848412075.

The spelling of 21158512 in words is "twenty-one million, one hundred fifty-eight thousand, five hundred twelve".