21353428186 has 4 divisors (see below), whose sum is σ = 32030142282. Its totient is φ = 10676714092.

The previous prime is 21353428157. The next prime is 21353428189. The reversal of 21353428186 is 68182435312.

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., 19405883025 + 1947545161 = 139305^2 + 44131^2 .

It is not an unprimeable number, because it can be changed into a prime (21353428189) by changing a digit.

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, 5338357045 + ... + 5338357048.

Almost surely, 2^21353428186 is an apocalyptic number.

21353428186 is a deficient number, since it is larger than the sum of its proper divisors (10676714096).

21353428186 is a wasteful number, since it uses less digits than its factorization.

21353428186 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10676714095.

The product of its digits is 276480, while the sum is 43.

The spelling of 21353428186 in words is "twenty-one billion, three hundred fifty-three million, four hundred twenty-eight thousand, one hundred eighty-six".