121517956218 has 32 divisors (see below), whose sum is σ = 243325031040. Its totient is φ = 40457833920.

The previous prime is 121517956199. The next prime is 121517956247. The reversal of 121517956218 is 812659715121.

It is a super-2 number, since 2×121517956218² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31800748 + ... + 31804568.

It is an arithmetic number, because the mean of its divisors is an integer number (7603907220).

Almost surely, 2^121517956218 is an apocalyptic number.

121517956218 is an abundant number, since it is smaller than the sum of its proper divisors (121807074822).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121517956218 is a wasteful number, since it uses less digits than its factorization.

121517956218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8742.

The product of its digits is 302400, while the sum is 48.

The spelling of 121517956218 in words is "one hundred twenty-one billion, five hundred seventeen million, nine hundred fifty-six thousand, two hundred eighteen".