1020217021 has 8 divisors (see below), whose sum is σ = 1048502840. Its totient is φ = 991968768.

The previous prime is 1020217019. The next prime is 1020217031. The reversal of 1020217021 is 1207120201.

It can be written as a sum of positive squares in 4 ways, for example, as 309408100 + 710808921 = 17590^2 + 26661^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1020217021 - 2¹ = 1020217019 is a prime.

It is a super-2 number, since 2×1020217021² = 2081685539876228882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1020216986 and 1020217004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020217031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50965 + ... + 68101.

It is an arithmetic number, because the mean of its divisors is an integer number (131062855).

Almost surely, 2^1020217021 is an apocalyptic number.

It is an amenable number.

1020217021 is a deficient number, since it is larger than the sum of its proper divisors (28285819).

1020217021 is a wasteful number, since it uses less digits than its factorization.

1020217021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18783.

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 1020217021 is about 31940.8362601858. The cubic root of 1020217021 is about 1006.6940960880.

Adding to 1020217021 its reverse (1207120201), we get a palindrome (2227337222).

The spelling of 1020217021 in words is "one billion, twenty million, two hundred seventeen thousand, twenty-one".