100121661 has 12 divisors (see below), whose sum is σ = 149285760. Its totient is φ = 64594440.

The previous prime is 100121639. The next prime is 100121669. The reversal of 100121661 is 166121001.

100121661 is a `hidden beast` number, since 1 + 0 + 0 + 1 + 2 + 1 + 661 = 666.

It is not a de Polignac number, because 100121661 - 2⁷ = 100121533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100121669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 179151 + ... + 179708.

It is an arithmetic number, because the mean of its divisors is an integer number (12440480).

Almost surely, 2^100121661 is an apocalyptic number.

It is an amenable number.

100121661 is a deficient number, since it is larger than the sum of its proper divisors (49164099).

100121661 is a wasteful number, since it uses less digits than its factorization.

100121661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358896 (or 358893 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 100121661 is about 10006.0812009498. The cubic root of 100121661 is about 464.3470405236.

Adding to 100121661 its reverse (166121001), we get a palindrome (266242662).

The spelling of 100121661 in words is "one hundred million, one hundred twenty-one thousand, six hundred sixty-one".