100203421 has 4 divisors (see below), whose sum is σ = 100421244. Its totient is φ = 99985600.

The previous prime is 100203407. The next prime is 100203427. The reversal of 100203421 is 124302001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 124302001 = 139 ⋅894259.

It can be written as a sum of positive squares in 2 ways, for example, as 10692900 + 89510521 = 3270^2 + 9461^2 .

It is a cyclic number.

It is not a de Polignac number, because 100203421 - 2¹¹ = 100201373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100203427) 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 3 ways as a sum of consecutive naturals, for example, 108220 + ... + 109141.

It is an arithmetic number, because the mean of its divisors is an integer number (25105311).

Almost surely, 2^100203421 is an apocalyptic number.

It is an amenable number.

100203421 is a deficient number, since it is larger than the sum of its proper divisors (217823).

100203421 is an equidigital number, since it uses as much as digits as its factorization.

100203421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217822.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 100203421 is about 10010.1658827414. The cubic root of 100203421 is about 464.4734024057.

Adding to 100203421 its reverse (124302001), we get a palindrome (224505422).

The spelling of 100203421 in words is "one hundred million, two hundred three thousand, four hundred twenty-one".