1012020021 has 8 divisors (see below), whose sum is σ = 1499288960. Its totient is φ = 674679996.

The previous prime is 1012020019. The next prime is 1012020029. The reversal of 1012020021 is 1200202101.

1012020021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1012020021 - 2¹ = 1012020019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1012019985 and 1012020012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1012020029) 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, 18741085 + ... + 18741138.

It is an arithmetic number, because the mean of its divisors is an integer number (187411120).

Almost surely, 2^1012020021 is an apocalyptic number.

It is an amenable number.

1012020021 is a deficient number, since it is larger than the sum of its proper divisors (487268939).

1012020021 is an equidigital number, since it uses as much as digits as its factorization.

1012020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37482232 (or 37482226 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1012020021 is about 31812.2621169888. The cubic root of 1012020021 is about 1003.9907265827.

Adding to 1012020021 its reverse (1200202101), we get a palindrome (2212222122).

The spelling of 1012020021 in words is "one billion, twelve million, twenty thousand, twenty-one".