121998408 has 32 divisors (see below), whose sum is σ = 348567360. Its totient is φ = 34856640.

The previous prime is 121998407. The next prime is 121998419. The reversal of 121998408 is 804899121.

It is a super-2 number, since 2×121998408² = 29767223109068928, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 121998408.

It is not an unprimeable number, because it can be changed into a prime (121998407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 362923 + ... + 363258.

It is an arithmetic number, because the mean of its divisors is an integer number (10892730).

Almost surely, 2^121998408 is an apocalyptic number.

It is an amenable number.

121998408 is an abundant number, since it is smaller than the sum of its proper divisors (226568952).

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

121998408 is a wasteful number, since it uses less digits than its factorization.

121998408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 726197 (or 726193 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 42.

The square root of 121998408 is about 11045.2889504983. The cubic root of 121998408 is about 495.9654090514.

The spelling of 121998408 in words is "one hundred twenty-one million, nine hundred ninety-eight thousand, four hundred eight".