2001011021021 has 8 divisors (see below), whose sum is σ = 2061674957304. Its totient is φ = 1941245809920.

The previous prime is 2001011021017. The next prime is 2001011021047. The reversal of 2001011021021 is 1201201101002.

It can be written as a sum of positive squares in 4 ways, for example, as 22166743225 + 1978844277796 = 148885^2 + 1406714^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2001011021021 - 2² = 2001011021017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001011020993 and 2001011021011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001011021521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 224676776 + ... + 224685681.

It is an arithmetic number, because the mean of its divisors is an integer number (257709369663).

Almost surely, 2^{2001011021021} is an apocalyptic number.

It is an amenable number.

2001011021021 is a deficient number, since it is larger than the sum of its proper divisors (60663936283).

2001011021021 is an equidigital number, since it uses as much as digits as its factorization.

2001011021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449362591.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 2001011021021 its reverse (1201201101002), we get a palindrome (3202212122023).

The spelling of 2001011021021 in words is "two trillion, one billion, eleven million, twenty-one thousand, twenty-one".