617261405681 has 2 divisors, whose sum is σ = 617261405682. Its totient is φ = 617261405680.

The previous prime is 617261405671. The next prime is 617261405687. The reversal of 617261405681 is 186504162716.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 424342805056 + 192918600625 = 651416^2 + 439225^2 .

It is a cyclic number.

It is not a de Polignac number, because 617261405681 - 2³⁰ = 616187663857 is a prime.

It is a super-2 number, since 2×617261405681² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (617261405687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 308630702840 + 308630702841.

It is an arithmetic number, because the mean of its divisors is an integer number (308630702841).

Almost surely, 2^617261405681 is an apocalyptic number.

It is an amenable number.

617261405681 is a deficient number, since it is larger than the sum of its proper divisors (1).

617261405681 is an equidigital number, since it uses as much as digits as its factorization.

617261405681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 483840, while the sum is 47.

The spelling of 617261405681 in words is "six hundred seventeen billion, two hundred sixty-one million, four hundred five thousand, six hundred eighty-one".