100121210001 has 40 divisors (see below), whose sum is σ = 157525435584. Its totient is φ = 63248597280.

The previous prime is 100121209957. The next prime is 100121210003. The reversal of 100121210001 is 100012121001.

It is a happy number.

It is not a de Polignac number, because 100121210001 - 2¹⁷ = 100121078929 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (100121210003) 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 39 ways as a sum of consecutive naturals, for example, 51790 + ... + 450471.

Almost surely, 2^100121210001 is an apocalyptic number.

It is an amenable number.

100121210001 is a deficient number, since it is larger than the sum of its proper divisors (57404225583).

100121210001 is a wasteful number, since it uses less digits than its factorization.

100121210001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502403 (or 502394 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 100121210001 its reverse (100012121001), we get a palindrome (200133331002).

It can be divided in two parts, 10012121000 and 1, that added together give a palindrome (10012121001).

The spelling of 100121210001 in words is "one hundred billion, one hundred twenty-one million, two hundred ten thousand, one".