1001001201021 has 12 divisors (see below), whose sum is σ = 1447102617948. Its totient is φ = 666774752064.

The previous prime is 1001001200957. The next prime is 1001001201023. The reversal of 1001001201021 is 1201021001001.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 702262436121 + 298738764900 = 838011^2 + 546570^2 .

It is not a de Polignac number, because 1001001201021 - 2⁶ = 1001001200957 is a prime.

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

It is a junction number, because it is equal to n+sod(n) for n = 1001001200994 and 1001001201012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001001201023) 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, 46603830 + ... + 46625303.

It is an arithmetic number, because the mean of its divisors is an integer number (120591884829).

Almost surely, 2^{1001001201021} is an apocalyptic number.

It is an amenable number.

1001001201021 is a deficient number, since it is larger than the sum of its proper divisors (446101416927).

1001001201021 is a wasteful number, since it uses less digits than its factorization.

1001001201021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93230332 (or 93230329 counting only the distinct ones).

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

Adding to 1001001201021 its reverse (1201021001001), we get a palindrome (2202022202022).

The spelling of 1001001201021 in words is "one trillion, one billion, one million, two hundred one thousand, twenty-one".