61881995311121 has 2 divisors, whose sum is σ = 61881995311122. Its totient is φ = 61881995311120.

The previous prime is 61881995311099. The next prime is 61881995311133. The reversal of 61881995311121 is 12111359918816.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61806405507025 + 75589804096 = 7861705^2 + 274936^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61881995311121 is a prime.

It is a super-3 number, since 3×61881995311121³ (a number of 42 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (61881995311151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30940997655560 + 30940997655561.

It is an arithmetic number, because the mean of its divisors is an integer number (30940997655561).

Almost surely, 2^{61881995311121} is an apocalyptic number.

It is an amenable number.

61881995311121 is a deficient number, since it is larger than the sum of its proper divisors (1).

61881995311121 is an equidigital number, since it uses as much as digits as its factorization.

61881995311121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 933120, while the sum is 56.

The spelling of 61881995311121 in words is "sixty-one trillion, eight hundred eighty-one billion, nine hundred ninety-five million, three hundred eleven thousand, one hundred twenty-one".