100204021 has 4 divisors (see below), whose sum is σ = 100764000. Its totient is φ = 99644044.

The previous prime is 100204009. The next prime is 100204033. The reversal of 100204021 is 120402001.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (100204009) and next prime (100204033).

It is a cyclic number.

It is not a de Polignac number, because 100204021 - 2⁵ = 100203989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 100203989 and 100204007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100274021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 279721 + ... + 280078.

It is an arithmetic number, because the mean of its divisors is an integer number (25191000).

Almost surely, 2^100204021 is an apocalyptic number.

It is an amenable number.

100204021 is a deficient number, since it is larger than the sum of its proper divisors (559979).

100204021 is an equidigital number, since it uses as much as digits as its factorization.

100204021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559978.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 100204021 is about 10010.1958522299. The cubic root of 100204021 is about 464.4743294648.

Adding to 100204021 its reverse (120402001), we get a palindrome (220606022).

It can be divided in two parts, 10020 and 4021, that added together give a palindrome (14041).

The spelling of 100204021 in words is "one hundred million, two hundred four thousand, twenty-one".