100400321 has 4 divisors (see below), whose sum is σ = 114743232. Its totient is φ = 86057412.

The previous prime is 100400273. The next prime is 100400323. The reversal of 100400321 is 123004001.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 123004001 = 31 ⋅3967871.

It is not a de Polignac number, because 100400321 - 2⁶ = 100400257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100400323) 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, 7171445 + ... + 7171458.

It is an arithmetic number, because the mean of its divisors is an integer number (28685808).

Almost surely, 2^100400321 is an apocalyptic number.

It is an amenable number.

100400321 is a deficient number, since it is larger than the sum of its proper divisors (14342911).

100400321 is an equidigital number, since it uses as much as digits as its factorization.

100400321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14342910.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 100400321 is about 10019.9960578835. The cubic root of 100400321 is about 464.7774338594. Note that the first 3 decimals are identical.

Adding to 100400321 its reverse (123004001), we get a palindrome (223404322).

The spelling of 100400321 in words is "one hundred million, four hundred thousand, three hundred twenty-one".