561663615451331 has 2 divisors, whose sum is σ = 561663615451332. Its totient is φ = 561663615451330.

The previous prime is 561663615451319. The next prime is 561663615451333. The reversal of 561663615451331 is 133154516366165.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 561663615451331 - 2¹⁰ = 561663615450307 is a prime.

It is a super-2 number, since 2×561663615451331² (a number of 30 digits) contains 22 as substring.

Together with 561663615451333, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (561663615451333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280831807725665 + 280831807725666.

It is an arithmetic number, because the mean of its divisors is an integer number (280831807725666).

Almost surely, 2^{561663615451331} is an apocalyptic number.

561663615451331 is a deficient number, since it is larger than the sum of its proper divisors (1).

561663615451331 is an equidigital number, since it uses as much as digits as its factorization.

561663615451331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17496000, while the sum is 56.

The spelling of 561663615451331 in words is "five hundred sixty-one trillion, six hundred sixty-three billion, six hundred fifteen million, four hundred fifty-one thousand, three hundred thirty-one".