21457898611 has 4 divisors (see below), whose sum is σ = 21474317592. Its totient is φ = 21441479632.

The previous prime is 21457898563. The next prime is 21457898647. The reversal of 21457898611 is 11689875412.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21457898611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21457898681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8207530 + ... + 8210143.

It is an arithmetic number, because the mean of its divisors is an integer number (5368579398).

Almost surely, 2^21457898611 is an apocalyptic number.

21457898611 is a deficient number, since it is larger than the sum of its proper divisors (16418981).

21457898611 is a wasteful number, since it uses less digits than its factorization.

21457898611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16418980.

The product of its digits is 967680, while the sum is 52.

The spelling of 21457898611 in words is "twenty-one billion, four hundred fifty-seven million, eight hundred ninety-eight thousand, six hundred eleven".