121815181281 has 8 divisors (see below), whose sum is σ = 163327618080. Its totient is φ = 80756432672.

The previous prime is 121815181277. The next prime is 121815181333. The reversal of 121815181281 is 182181518121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121815181281 - 2² = 121815181277 is a prime.

It is a super-2 number, since 2×121815181281² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (121815181381) 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 7 ways as a sum of consecutive naturals, for example, 113421420 + ... + 113422493.

It is an arithmetic number, because the mean of its divisors is an integer number (20415952260).

Almost surely, 2^121815181281 is an apocalyptic number.

It is an amenable number.

121815181281 is a deficient number, since it is larger than the sum of its proper divisors (41512436799).

121815181281 is a wasteful number, since it uses less digits than its factorization.

121815181281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226844095.

The product of its digits is 10240, while the sum is 39.

The spelling of 121815181281 in words is "one hundred twenty-one billion, eight hundred fifteen million, one hundred eighty-one thousand, two hundred eighty-one".