21031345067 has 4 divisors (see below), whose sum is σ = 21041868000. Its totient is φ = 21020822136.

The previous prime is 21031345063. The next prime is 21031345073. The reversal of 21031345067 is 76054313012.

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

It is a cyclic number.

It is not a de Polignac number, because 21031345067 - 2² = 21031345063 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21031345063) 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, 5258468 + ... + 5262465.

It is an arithmetic number, because the mean of its divisors is an integer number (5260467000).

Almost surely, 2^21031345067 is an apocalyptic number.

21031345067 is a deficient number, since it is larger than the sum of its proper divisors (10522933).

21031345067 is a wasteful number, since it uses less digits than its factorization.

21031345067 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10522932.

The product of its (nonzero) digits is 15120, while the sum is 32.

Adding to 21031345067 its reverse (76054313012), we get a palindrome (97085658079).

The spelling of 21031345067 in words is "twenty-one billion, thirty-one million, three hundred forty-five thousand, sixty-seven".