21621772267117 has 8 divisors (see below), whose sum is σ = 24089247245952. Its totient is φ = 19237940508000.

The previous prime is 21621772267061. The next prime is 21621772267129. The reversal of 21621772267117 is 71176227712612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21621772267117 - 2⁷ = 21621772266989 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 (21621772267517) 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 7 ways as a sum of consecutive naturals, for example, 20910804384 + ... + 20910805417.

It is an arithmetic number, because the mean of its divisors is an integer number (3011155905744).

Almost surely, 2^{21621772267117} is an apocalyptic number.

It is an amenable number.

21621772267117 is a deficient number, since it is larger than the sum of its proper divisors (2467474978835).

21621772267117 is a wasteful number, since it uses less digits than its factorization.

21621772267117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41821609859.

The product of its digits is 1382976, while the sum is 52.

Adding to 21621772267117 its reverse (71176227712612), we get a palindrome (92797999979729).

The spelling of 21621772267117 in words is "twenty-one trillion, six hundred twenty-one billion, seven hundred seventy-two million, two hundred sixty-seven thousand, one hundred seventeen".