1010020021 has 4 divisors (see below), whose sum is σ = 1042601344. Its totient is φ = 977438700.

The previous prime is 1010020019. The next prime is 1010020027. The reversal of 1010020021 is 1200200101.

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 1010020021 - 2¹ = 1010020019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1010019986 and 1010020013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1010020027) 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, 16290615 + ... + 16290676.

It is an arithmetic number, because the mean of its divisors is an integer number (260650336).

Almost surely, 2^1010020021 is an apocalyptic number.

It is an amenable number.

1010020021 is a deficient number, since it is larger than the sum of its proper divisors (32581323).

1010020021 is an equidigital number, since it uses as much as digits as its factorization.

1010020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32581322.

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

The square root of 1010020021 is about 31780.8121513595. The cubic root of 1010020021 is about 1003.3289130413.

Adding to 1010020021 its reverse (1200200101), we get a palindrome (2210220122).

The spelling of 1010020021 in words is "one billion, ten million, twenty thousand, twenty-one".