100120581 has 48 divisors (see below), whose sum is σ = 163650240. Its totient is φ = 58464000.

The previous prime is 100120561. The next prime is 100120583. The reversal of 100120581 is 185021001.

It is not a de Polignac number, because 100120581 - 2¹⁰ = 100119557 is a prime.

It is a super-2 number, since 2×100120581² = 20048261479555122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100120583) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 356161 + ... + 356441.

It is an arithmetic number, because the mean of its divisors is an integer number (3409380).

Almost surely, 2^100120581 is an apocalyptic number.

100120581 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

100120581 is a deficient number, since it is larger than the sum of its proper divisors (63529659).

100120581 is a wasteful number, since it uses less digits than its factorization.

100120581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 415 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 18.

The square root of 100120581 is about 10006.0272336227. The cubic root of 100120581 is about 464.3453708996.

Adding to 100120581 its reverse (185021001), we get a palindrome (285141582).

The spelling of 100120581 in words is "one hundred million, one hundred twenty thousand, five hundred eighty-one".