617261722221 has 16 divisors (see below), whose sum is σ = 830351857536. Its totient is φ = 407840165376.

The previous prime is 617261722211. The next prime is 617261722243. The reversal of 617261722221 is 122227162716.

It is a happy number.

It is not a de Polignac number, because 617261722221 - 2⁷ = 617261722093 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 617261722221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (617261722211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6295056 + ... + 6392358.

It is an arithmetic number, because the mean of its divisors is an integer number (51896991096).

Almost surely, 2^617261722221 is an apocalyptic number.

It is an amenable number.

617261722221 is a deficient number, since it is larger than the sum of its proper divisors (213090135315).

617261722221 is a wasteful number, since it uses less digits than its factorization.

617261722221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116132.

The product of its digits is 56448, while the sum is 39.

Adding to 617261722221 its reverse (122227162716), we get a palindrome (739488884937).

The spelling of 617261722221 in words is "six hundred seventeen billion, two hundred sixty-one million, seven hundred twenty-two thousand, two hundred twenty-one".