21364171447636 has 12 divisors (see below), whose sum is σ = 39586552976628. Its totient is φ = 10053727740032.

The previous prime is 21364171447631. The next prime is 21364171447637. The reversal of 21364171447636 is 63674417146312.

It can be written as a sum of positive squares in 2 ways, for example, as 19532598984900 + 1831572462736 = 4419570^2 + 1353356^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21364171447631) 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, 157089495871 + ... + 157089496006.

It is an arithmetic number, because the mean of its divisors is an integer number (3298879414719).

Almost surely, 2^{21364171447636} is an apocalyptic number.

It is an amenable number.

21364171447636 is a deficient number, since it is larger than the sum of its proper divisors (18222381528992).

21364171447636 is a wasteful number, since it uses less digits than its factorization.

21364171447636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314178991898 (or 314178991896 counting only the distinct ones).

The product of its digits is 12192768, while the sum is 55.

The spelling of 21364171447636 in words is "twenty-one trillion, three hundred sixty-four billion, one hundred seventy-one million, four hundred forty-seven thousand, six hundred thirty-six".