100400401 has 4 divisors (see below), whose sum is σ = 101040052. Its totient is φ = 99760752.

The previous prime is 100400393. The next prime is 100400437. The reversal of 100400401 is 104004001.

It is a Cunningham number, because it is equal to 10020²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 104004001 = 281 ⋅370121.

It can be written as a sum of positive squares in 2 ways, for example, as 29419776 + 70980625 = 5424^2 + 8425^2 .

It is a cyclic number.

It is not a de Polignac number, because 100400401 - 2³ = 100400393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100400491) 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, 319590 + ... + 319903.

It is an arithmetic number, because the mean of its divisors is an integer number (25260013).

Almost surely, 2^100400401 is an apocalyptic number.

It is an amenable number.

100400401 is a deficient number, since it is larger than the sum of its proper divisors (639651).

100400401 is an equidigital number, since it uses as much as digits as its factorization.

100400401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 639650.

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

The square root of 100400401 is about 10020.0000499002. Note that the first 4 decimals coincide. The cubic root of 100400401 is about 464.7775573058. Note that the first 3 decimals are identical.

Adding to 100400401 its reverse (104004001), we get a palindrome (204404402).

The spelling of 100400401 in words is "one hundred million, four hundred thousand, four hundred one".