121998550 has 24 divisors (see below), whose sum is σ = 227844792. Its totient is φ = 48600000.

The previous prime is 121998533. The next prime is 121998551. The reversal of 121998550 is 55899121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121998551) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7690 + ... + 17410.

It is an arithmetic number, because the mean of its divisors is an integer number (9493533).

Almost surely, 2^121998550 is an apocalyptic number.

121998550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

121998550 is a deficient number, since it is larger than the sum of its proper divisors (105846242).

121998550 is a wasteful number, since it uses less digits than its factorization.

121998550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9984 (or 9979 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 40.

The square root of 121998550 is about 11045.2953785763. The cubic root of 121998550 is about 495.9656014776.

The spelling of 121998550 in words is "one hundred twenty-one million, nine hundred ninety-eight thousand, five hundred fifty".