121555272681 has 12 divisors (see below), whose sum is σ = 178555768560. Its totient is φ = 79663342200.

The previous prime is 121555272673. The next prime is 121555272697. The reversal of 121555272681 is 186272555121.

It is a happy number.

121555272681 is a `hidden beast` number, since 1 + 2 + 15 + 552 + 7 + 2 + 6 + 81 = 666.

It is not a de Polignac number, because 121555272681 - 2³ = 121555272673 is a prime.

It is a super-2 number, since 2×121555272681² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (121555272661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 114458295 + ... + 114459356.

It is an arithmetic number, because the mean of its divisors is an integer number (14879647380).

Almost surely, 2^121555272681 is an apocalyptic number.

It is an amenable number.

121555272681 is a deficient number, since it is larger than the sum of its proper divisors (57000495879).

121555272681 is a wasteful number, since it uses less digits than its factorization.

121555272681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228917716 (or 228917713 counting only the distinct ones).

The product of its digits is 336000, while the sum is 45.

The spelling of 121555272681 in words is "one hundred twenty-one billion, five hundred fifty-five million, two hundred seventy-two thousand, six hundred eighty-one".