21621266274317 has 4 divisors (see below), whose sum is σ = 21621285652320. Its totient is φ = 21621246896316.

The previous prime is 21621266274253. The next prime is 21621266274323. The reversal of 21621266274317 is 71347266212612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21621266274317 - 2⁶ = 21621266274253 is a prime.

It is a super-3 number, since 3×21621266274317³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21621266274347) 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, 7905983 + ... + 10283340.

It is an arithmetic number, because the mean of its divisors is an integer number (5405321413080).

Almost surely, 2^{21621266274317} is an apocalyptic number.

It is an amenable number.

21621266274317 is a deficient number, since it is larger than the sum of its proper divisors (19378003).

21621266274317 is a wasteful number, since it uses less digits than its factorization.

21621266274317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19378002.

The product of its digits is 2032128, while the sum is 50.

The spelling of 21621266274317 in words is "twenty-one trillion, six hundred twenty-one billion, two hundred sixty-six million, two hundred seventy-four thousand, three hundred seventeen".