100031805 has 12 divisors (see below), whose sum is σ = 173388540. Its totient is φ = 53350272.

The previous prime is 100031801. The next prime is 100031809. The reversal of 100031805 is 508130001.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (100031801) and next prime (100031809).

It can be written as a sum of positive squares in 2 ways, for example, as 44275716 + 55756089 = 6654^2 + 7467^2 .

It is not a de Polignac number, because 100031805 - 2² = 100031801 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100031801) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1111420 + ... + 1111509.

It is an arithmetic number, because the mean of its divisors is an integer number (14449045).

Almost surely, 2^100031805 is an apocalyptic number.

100031805 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

100031805 is a deficient number, since it is larger than the sum of its proper divisors (73356735).

100031805 is a wasteful number, since it uses less digits than its factorization.

100031805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2222940 (or 2222937 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 100031805 is about 10001.5901235754. The cubic root of 100031805 is about 464.2080867229.

Adding to 100031805 its reverse (508130001), we get a palindrome (608161806).

The spelling of 100031805 in words is "one hundred million, thirty-one thousand, eight hundred five".