21621401714217 has 4 divisors (see below), whose sum is σ = 28828535618960. Its totient is φ = 14414267809476.

The previous prime is 21621401714153. The next prime is 21621401714221. The reversal of 21621401714217 is 71241710412612.

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 not a de Polignac number, because 21621401714217 - 2⁶ = 21621401714153 is a prime.

It is a super-2 number, since 2×21621401714217² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21621401714267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3603566952367 + ... + 3603566952372.

It is an arithmetic number, because the mean of its divisors is an integer number (7207133904740).

Almost surely, 2^{21621401714217} is an apocalyptic number.

It is an amenable number.

21621401714217 is a deficient number, since it is larger than the sum of its proper divisors (7207133904743).

21621401714217 is an equidigital number, since it uses as much as digits as its factorization.

21621401714217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7207133904742.

The product of its (nonzero) digits is 37632, while the sum is 39.

The spelling of 21621401714217 in words is "twenty-one trillion, six hundred twenty-one billion, four hundred one million, seven hundred fourteen thousand, two hundred seventeen".