21049576186 has 4 divisors (see below), whose sum is σ = 31574364282. Its totient is φ = 10524788092.

The previous prime is 21049576153. The next prime is 21049576199. The reversal of 21049576186 is 68167594012.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 20784700561 + 264875625 = 144169^2 + 16275^2 .

It is a super-2 number, since 2×21049576186² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5262394045 + ... + 5262394048.

Almost surely, 2^21049576186 is an apocalyptic number.

21049576186 is a deficient number, since it is larger than the sum of its proper divisors (10524788096).

21049576186 is a wasteful number, since it uses less digits than its factorization.

21049576186 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10524788095.

The product of its (nonzero) digits is 725760, while the sum is 49.

The spelling of 21049576186 in words is "twenty-one billion, forty-nine million, five hundred seventy-six thousand, one hundred eighty-six".