100500021 has 10 divisors (see below), whose sum is σ = 150129782. Its totient is φ = 66999960.

The previous prime is 100500019. The next prime is 100500121. The reversal of 100500021 is 120005001.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 73719396 + 26780625 = 8586^2 + 5175^2 .

It is not a de Polignac number, because 100500021 - 2¹ = 100500019 is a prime.

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

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 100499976 and 100500012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100500011) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 620290 + ... + 620451.

Almost surely, 2^100500021 is an apocalyptic number.

It is an amenable number.

100500021 is a deficient number, since it is larger than the sum of its proper divisors (49629761).

100500021 is an equidigital number, since it uses as much as digits as its factorization.

100500021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1240753 (or 1240744 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 9.

The square root of 100500021 is about 10024.9698752665. The cubic root of 100500021 is about 464.9312281228.

Adding to 100500021 its reverse (120005001), we get a palindrome (220505022).

The spelling of 100500021 in words is "one hundred million, five hundred thousand, twenty-one".