1001020121001 has 12 divisors (see below), whose sum is σ = 1445958570628. Its totient is φ = 667328000544.

The previous prime is 1001020120957. The next prime is 1001020121021. The reversal of 1001020121001 is 1001210201001.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 136566463401 + 864453657600 = 369549^2 + 929760^2 .

It is not a de Polignac number, because 1001020121001 - 2⁹ = 1001020120489 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 (1001020121021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1220110 + ... + 1868343.

Almost surely, 2^{1001020121001} is an apocalyptic number.

It is an amenable number.

1001020121001 is a deficient number, since it is larger than the sum of its proper divisors (444938449627).

1001020121001 is a wasteful number, since it uses less digits than its factorization.

1001020121001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3124472 (or 3124469 counting only the distinct ones).

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

Adding to 1001020121001 its reverse (1001210201001), we get a palindrome (2002230322002).

The spelling of 1001020121001 in words is "one trillion, one billion, twenty million, one hundred twenty-one thousand, one".