1020010021 has 4 divisors (see below), whose sum is σ = 1020140352. Its totient is φ = 1019879692.

The previous prime is 1020010007. The next prime is 1020010031. The reversal of 1020010021 is 1200100201.

1020010021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 1020010021 - 2²⁹ = 483139109 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1020009986 and 1020010013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020010031) 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, 52621 + ... + 69346.

It is an arithmetic number, because the mean of its divisors is an integer number (255035088).

Almost surely, 2^1020010021 is an apocalyptic number.

It is an amenable number.

1020010021 is a deficient number, since it is larger than the sum of its proper divisors (130331).

1020010021 is an equidigital number, since it uses as much as digits as its factorization.

1020010021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130330.

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 1020010021 is about 31937.5957297978. The cubic root of 1020010021 is about 1006.6260060742.

Adding to 1020010021 its reverse (1200100201), we get a palindrome (2220110222).

The spelling of 1020010021 in words is "one billion, twenty million, ten thousand, twenty-one".