100121553 has 36 divisors (see below), whose sum is σ = 175563648. Its totient is φ = 54719280.

The previous prime is 100121533. The next prime is 100121563. The reversal of 100121553 is 355121001.

100121553 is a `hidden beast` number, since 100 + 12 + 1 + 553 = 666.

It is not a de Polignac number, because 100121553 - 2⁵ = 100121521 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (100121533) 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 35 ways as a sum of consecutive naturals, for example, 5208 + ... + 15078.

It is an arithmetic number, because the mean of its divisors is an integer number (4876768).

Almost surely, 2^100121553 is an apocalyptic number.

It is an amenable number.

100121553 is a deficient number, since it is larger than the sum of its proper divisors (75442095).

100121553 is a wasteful number, since it uses less digits than its factorization.

100121553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9914 (or 9904 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 18.

The square root of 100121553 is about 10006.0758042301. The cubic root of 100121553 is about 464.3468735618.

Adding to 100121553 its reverse (355121001), we get a palindrome (455242554).

The spelling of 100121553 in words is "one hundred million, one hundred twenty-one thousand, five hundred fifty-three".