61331 has 2 divisors, whose sum is σ = 61332. Its totient is φ = 61330.

The previous prime is 61297. The next prime is 61333. The reversal of 61331 is 13316.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61331 is a prime.

It is a super-2 number, since 2×61331² = 7522983122, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 61333, 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 (61333) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30665 + 30666.

It is an arithmetic number, because the mean of its divisors is an integer number (30666).

2⁶¹³³¹ is an apocalyptic number.

61331 is a deficient number, since it is larger than the sum of its proper divisors (1).

61331 is an equidigital number, since it uses as much as digits as its factorization.

61331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54, while the sum is 14.

The square root of 61331 is about 247.6509640603. The cubic root of 61331 is about 39.4360445572.

Adding to 61331 its reverse (13316), we get a palindrome (74647).

The spelling of 61331 in words is "sixty-one thousand, three hundred thirty-one".