21305166411 has 24 divisors (see below), whose sum is σ = 30818280960. Its totient is φ = 13083498112.

The previous prime is 21305166397. The next prime is 21305166413. The reversal of 21305166411 is 11466150312.

It is a happy number.

It is not a de Polignac number, because 21305166411 - 2¹⁵ = 21305133643 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21305166413) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 220671 + ... + 302168.

It is an arithmetic number, because the mean of its divisors is an integer number (1284095040).

Almost surely, 2^21305166411 is an apocalyptic number.

21305166411 is a deficient number, since it is larger than the sum of its proper divisors (9513114549).

21305166411 is a wasteful number, since it uses less digits than its factorization.

21305166411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 522923 (or 522906 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The spelling of 21305166411 in words is "twenty-one billion, three hundred five million, one hundred sixty-six thousand, four hundred eleven".