100421221 has 2 divisors, whose sum is σ = 100421222. Its totient is φ = 100421220.

The previous prime is 100421201. The next prime is 100421231. The reversal of 100421221 is 122124001.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72437121 + 27984100 = 8511^2 + 5290^2 .

It is a cyclic number.

It is not a de Polignac number, because 100421221 - 2²³ = 92032613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100421201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50210610 + 50210611.

It is an arithmetic number, because the mean of its divisors is an integer number (50210611).

Almost surely, 2^100421221 is an apocalyptic number.

It is an amenable number.

100421221 is a deficient number, since it is larger than the sum of its proper divisors (1).

100421221 is an equidigital number, since it uses as much as digits as its factorization.

100421221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 100421221 is about 10021.0389181961. The cubic root of 100421221 is about 464.8096820113.

Adding to 100421221 its reverse (122124001), we get a palindrome (222545222).

The spelling of 100421221 in words is "one hundred million, four hundred twenty-one thousand, two hundred twenty-one".