1021031320021 has 4 divisors (see below), whose sum is σ = 1037769538444. Its totient is φ = 1004293101600.

The previous prime is 1021031319941. The next prime is 1021031320039. The reversal of 1021031320021 is 1200231301201.

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 78840777796 + 942190542225 = 280786^2 + 970665^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021031320021 - 2²⁵ = 1020997765589 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021031319977 and 1021031320004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021031320121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8369109120 + ... + 8369109241.

It is an arithmetic number, because the mean of its divisors is an integer number (259442384611).

Almost surely, 2^{1021031320021} is an apocalyptic number.

It is an amenable number.

1021031320021 is a deficient number, since it is larger than the sum of its proper divisors (16738218423).

1021031320021 is an equidigital number, since it uses as much as digits as its factorization.

1021031320021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16738218422.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 1021031320021 its reverse (1200231301201), we get a palindrome (2221262621222).

The spelling of 1021031320021 in words is "one trillion, twenty-one billion, thirty-one million, three hundred twenty thousand, twenty-one".