51661371331 has 2 divisors, whose sum is σ = 51661371332. Its totient is φ = 51661371330.

The previous prime is 51661371299. The next prime is 51661371361. The reversal of 51661371331 is 13317316615.

51661371331 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51661371331 - 2⁵ = 51661371299 is a prime.

It is a super-2 number, since 2×51661371331² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51661371361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25830685665 + 25830685666.

It is an arithmetic number, because the mean of its divisors is an integer number (25830685666).

Almost surely, 2^51661371331 is an apocalyptic number.

51661371331 is a deficient number, since it is larger than the sum of its proper divisors (1).

51661371331 is an equidigital number, since it uses as much as digits as its factorization.

51661371331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34020, while the sum is 37.

Adding to 51661371331 its reverse (13317316615), we get a palindrome (64978687946).

The spelling of 51661371331 in words is "fifty-one billion, six hundred sixty-one million, three hundred seventy-one thousand, three hundred thirty-one".