1021330021 has 4 divisors (see below), whose sum is σ = 1021413952. Its totient is φ = 1021246092.

The previous prime is 1021330001. The next prime is 1021330039. The reversal of 1021330021 is 1200331201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1200331201 = 563 ⋅2132027.

It is a cyclic number.

It is not a de Polignac number, because 1021330021 - 2⁵ = 1021329989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021329983 and 1021330010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021330001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19815 + ... + 49348.

It is an arithmetic number, because the mean of its divisors is an integer number (255353488).

Almost surely, 2^1021330021 is an apocalyptic number.

It is an amenable number.

1021330021 is a deficient number, since it is larger than the sum of its proper divisors (83931).

1021330021 is an equidigital number, since it uses as much as digits as its factorization.

1021330021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83930.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 1021330021 is about 31958.2543484465. The cubic root of 1021330021 is about 1007.0600454573.

Adding to 1021330021 its reverse (1200331201), we get a palindrome (2221661222).

The spelling of 1021330021 in words is "one billion, twenty-one million, three hundred thirty thousand, twenty-one".