100386821 has 4 divisors (see below), whose sum is σ = 100494444. Its totient is φ = 100279200.

The previous prime is 100386817. The next prime is 100386859. The reversal of 100386821 is 128683001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24453025 + 75933796 = 4945^2 + 8714^2 .

It is a cyclic number.

It is not a de Polignac number, because 100386821 - 2² = 100386817 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 (100386521) 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, 52400 + ... + 54281.

It is an arithmetic number, because the mean of its divisors is an integer number (25123611).

Almost surely, 2^100386821 is an apocalyptic number.

It is an amenable number.

100386821 is a deficient number, since it is larger than the sum of its proper divisors (107623).

100386821 is an equidigital number, since it uses as much as digits as its factorization.

100386821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107622.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 100386821 is about 10019.3223822772. The cubic root of 100386821 is about 464.7566013344.

The spelling of 100386821 in words is "one hundred million, three hundred eighty-six thousand, eight hundred twenty-one".