100215661 has 16 divisors (see below), whose sum is σ = 123596928. Its totient is φ = 79128000.

The previous prime is 100215649. The next prime is 100215679. The reversal of 100215661 is 166512001.

It is not a de Polignac number, because 100215661 - 2⁹ = 100215149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100215061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63006 + ... + 64576.

It is an arithmetic number, because the mean of its divisors is an integer number (7724808).

Almost surely, 2^100215661 is an apocalyptic number.

It is an amenable number.

100215661 is a deficient number, since it is larger than the sum of its proper divisors (23381267).

100215661 is a wasteful number, since it uses less digits than its factorization.

100215661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2292.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 100215661 is about 10010.7772425521. Note that the first 3 decimals coincide. The cubic root of 100215661 is about 464.4923136795.

Adding to 100215661 its reverse (166512001), we get a palindrome (266727662).

The spelling of 100215661 in words is "one hundred million, two hundred fifteen thousand, six hundred sixty-one".