100821418 has 4 divisors (see below), whose sum is σ = 151232130. Its totient is φ = 50410708.

The previous prime is 100821377. The next prime is 100821421. The reversal of 100821418 is 814128001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 814128001 = 2309 ⋅352589.

It can be written as a sum of positive squares in only one way, i.e., 71520849 + 29300569 = 8457^2 + 5413^2 .

It is a junction number, because it is equal to n+sod(n) for n = 100821392 and 100821401.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25205353 + ... + 25205356.

Almost surely, 2^100821418 is an apocalyptic number.

100821418 is a deficient number, since it is larger than the sum of its proper divisors (50410712).

100821418 is an equidigital number, since it uses as much as digits as its factorization.

100821418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50410711.

The product of its (nonzero) digits is 512, while the sum is 25.

The square root of 100821418 is about 10040.9869036863. The cubic root of 100821418 is about 465.4263142404.

Adding to 100821418 its reverse (814128001), we get a palindrome (914949419).

The spelling of 100821418 in words is "one hundred million, eight hundred twenty-one thousand, four hundred eighteen".