210001001121 has 12 divisors (see below), whose sum is σ = 311533017172. Its totient is φ = 136216865376.

The previous prime is 210001001083. The next prime is 210001001131. The reversal of 210001001121 is 121100100012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 122857961121 + 87143040000 = 350511^2 + 295200^2 .

It is not a de Polignac number, because 210001001121 - 2¹⁴ = 210000984737 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210001001131) 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 11 ways as a sum of consecutive naturals, for example, 315316486 + ... + 315317151.

Almost surely, 2^210001001121 is an apocalyptic number.

It is an amenable number.

210001001121 is a deficient number, since it is larger than the sum of its proper divisors (101532016051).

210001001121 is a wasteful number, since it uses less digits than its factorization.

210001001121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 630633680 (or 630633677 counting only the distinct ones).

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

Adding to 210001001121 its reverse (121100100012), we get a palindrome (331101101133).

It can be divided in two parts, 21000 and 1001121, that added together give a square (1022121 = 1011²).

The spelling of 210001001121 in words is "two hundred ten billion, one million, one thousand, one hundred twenty-one".