121998412154 has 8 divisors (see below), whose sum is σ = 183111356820. Its totient is φ = 60961293216.

The previous prime is 121998412099. The next prime is 121998412177. The reversal of 121998412154 is 451214899121.

It can be written as a sum of positive squares in 2 ways, for example, as 121706788225 + 291623929 = 348865^2 + 17077^2 .

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

It is a super-2 number, since 2×121998412154² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 121998412099 and 121998412108.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18952409 + ... + 18958844.

Almost surely, 2^121998412154 is an apocalyptic number.

121998412154 is a deficient number, since it is larger than the sum of its proper divisors (61112944666).

121998412154 is a wasteful number, since it uses less digits than its factorization.

121998412154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37912864.

The product of its digits is 207360, while the sum is 47.

The spelling of 121998412154 in words is "one hundred twenty-one billion, nine hundred ninety-eight million, four hundred twelve thousand, one hundred fifty-four".