21013782158 has 8 divisors (see below), whose sum is σ = 31524594240. Its totient is φ = 10505584080.

The previous prime is 21013782151. The next prime is 21013782253. The reversal of 21013782158 is 85128731012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013782151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 633278 + ... + 665633.

It is an arithmetic number, because the mean of its divisors is an integer number (3940574280).

Almost surely, 2^21013782158 is an apocalyptic number.

21013782158 is a deficient number, since it is larger than the sum of its proper divisors (10510812082).

21013782158 is a wasteful number, since it uses less digits than its factorization.

21013782158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1307002.

The product of its (nonzero) digits is 26880, while the sum is 38.

The spelling of 21013782158 in words is "twenty-one billion, thirteen million, seven hundred eighty-two thousand, one hundred fifty-eight".