1636327667221 has 4 divisors (see below), whose sum is σ = 1762199026252. Its totient is φ = 1510456308192.

The previous prime is 1636327667171. The next prime is 1636327667279. The reversal of 1636327667221 is 1227667236361.

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

It can be written as a sum of positive squares in 2 ways, for example, as 520293886596 + 1116033780625 = 721314^2 + 1056425^2 .

It is not a de Polignac number, because 1636327667221 - 2⁹ = 1636327666709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1636327667921) 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, 62935679496 + ... + 62935679521.

It is an arithmetic number, because the mean of its divisors is an integer number (440549756563).

Almost surely, 2^{1636327667221} is an apocalyptic number.

It is an amenable number.

1636327667221 is a deficient number, since it is larger than the sum of its proper divisors (125871359031).

1636327667221 is a wasteful number, since it uses less digits than its factorization.

1636327667221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125871359030.

The product of its digits is 4572288, while the sum is 52.

The spelling of 1636327667221 in words is "one trillion, six hundred thirty-six billion, three hundred twenty-seven million, six hundred sixty-seven thousand, two hundred twenty-one".