21140323634 has 8 divisors (see below), whose sum is σ = 31749685020. Its totient is φ = 10557095296.

The previous prime is 21140323597. The next prime is 21140323637. The reversal of 21140323634 is 43632304112.

It can be written as a sum of positive squares in 2 ways, for example, as 20356155625 + 784168009 = 142675^2 + 28003^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 21140323597 and 21140323606.

It is not an unprimeable number, because it can be changed into a prime (21140323637) 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 in 3 ways as a sum of consecutive naturals, for example, 6531239 + ... + 6534474.

Almost surely, 2^21140323634 is an apocalyptic number.

21140323634 is a deficient number, since it is larger than the sum of its proper divisors (10609361386).

21140323634 is a wasteful number, since it uses less digits than its factorization.

21140323634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13066524.

The product of its (nonzero) digits is 10368, while the sum is 29.

Adding to 21140323634 its reverse (43632304112), we get a palindrome (64772627746).

The spelling of 21140323634 in words is "twenty-one billion, one hundred forty million, three hundred twenty-three thousand, six hundred thirty-four".