121533504100 has 72 divisors (see below), whose sum is σ = 275446745280. Its totient is φ = 46497755520.

The previous prime is 121533504077. The next prime is 121533504109. The reversal of 121533504100 is 1405335121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (121533504109) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 60064 + ... + 496663.

It is an arithmetic number, because the mean of its divisors is an integer number (3825649240).

Almost surely, 2^121533504100 is an apocalyptic number.

121533504100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121533504100 is an abundant number, since it is smaller than the sum of its proper divisors (153913241180).

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

121533504100 is a wasteful number, since it uses less digits than its factorization.

121533504100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556837 (or 556830 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

Adding to 121533504100 its reverse (1405335121), we get a palindrome (122938839221).

The spelling of 121533504100 in words is "one hundred twenty-one billion, five hundred thirty-three million, five hundred four thousand, one hundred".