1021020021001 has 4 divisors (see below), whose sum is σ = 1021285018372. Its totient is φ = 1020755023632.

The previous prime is 1021020020957. The next prime is 1021020021053. The reversal of 1021020021001 is 1001200201201.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 832619750400 + 188400270601 = 912480^2 + 434051^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021020021001 - 2²⁵ = 1020986466569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1021020021101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 132492906 + ... + 132500611.

It is an arithmetic number, because the mean of its divisors is an integer number (255321254593).

Almost surely, 2^{1021020021001} is an apocalyptic number.

It is an amenable number.

1021020021001 is a deficient number, since it is larger than the sum of its proper divisors (264997371).

1021020021001 is an equidigital number, since it uses as much as digits as its factorization.

1021020021001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264997370.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 1021020021001 its reverse (1001200201201), we get a palindrome (2022220222202).

The spelling of 1021020021001 in words is "one trillion, twenty-one billion, twenty million, twenty-one thousand, one".