121557782771 has 2 divisors, whose sum is σ = 121557782772. Its totient is φ = 121557782770.

The previous prime is 121557782693. The next prime is 121557782809. The reversal of 121557782771 is 177287755121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 121557782771 - 2¹⁰ = 121557781747 is a prime.

It is not a weakly prime, because it can be changed into another prime (121557781771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60778891385 + 60778891386.

It is an arithmetic number, because the mean of its divisors is an integer number (60778891386).

Almost surely, 2^121557782771 is an apocalyptic number.

121557782771 is a deficient number, since it is larger than the sum of its proper divisors (1).

121557782771 is an equidigital number, since it uses as much as digits as its factorization.

121557782771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1920800, while the sum is 53.

The spelling of 121557782771 in words is "one hundred twenty-one billion, five hundred fifty-seven million, seven hundred eighty-two thousand, seven hundred seventy-one".