21398567611 has 4 divisors (see below), whose sum is σ = 21419164000. Its totient is φ = 21377971224.

The previous prime is 21398567587. The next prime is 21398567621. The reversal of 21398567611 is 11676589312.

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 21398567611 - 2⁷ = 21398567483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21398567621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10296636 + ... + 10298713.

It is an arithmetic number, because the mean of its divisors is an integer number (5354791000).

Almost surely, 2^21398567611 is an apocalyptic number.

21398567611 is a deficient number, since it is larger than the sum of its proper divisors (20596389).

21398567611 is a wasteful number, since it uses less digits than its factorization.

21398567611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20596388.

The product of its digits is 544320, while the sum is 49.

The spelling of 21398567611 in words is "twenty-one billion, three hundred ninety-eight million, five hundred sixty-seven thousand, six hundred eleven".