100013121 has 24 divisors (see below), whose sum is σ = 156647400. Its totient is φ = 61122816.

The previous prime is 100013113. The next prime is 100013143. The reversal of 100013121 is 121310001.

It can be written as a sum of positive squares in 4 ways, for example, as 12852225 + 87160896 = 3585^2 + 9336^2 .

It is not a de Polignac number, because 100013121 - 2³ = 100013113 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (100013021) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14565 + ... + 20301.

It is an arithmetic number, because the mean of its divisors is an integer number (6526975).

Almost surely, 2^100013121 is an apocalyptic number.

It is an amenable number.

100013121 is a deficient number, since it is larger than the sum of its proper divisors (56634279).

100013121 is a wasteful number, since it uses less digits than its factorization.

100013121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5905 (or 5902 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 9.

The square root of 100013121 is about 10000.6560284813. The cubic root of 100013121 is about 464.1791832358.

Adding to 100013121 its reverse (121310001), we get a palindrome (221323122).

The spelling of 100013121 in words is "one hundred million, thirteen thousand, one hundred twenty-one".