1020021011 has 4 divisors (see below), whose sum is σ = 1021110552. Its totient is φ = 1018931472.

The previous prime is 1020020983. The next prime is 1020021127. The reversal of 1020021011 is 1101200201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1101200201 = 43 ⋅25609307.

It is a cyclic number.

It is not a de Polignac number, because 1020021011 - 2¹⁸ = 1019758867 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1020021011.

It is not an unprimeable number, because it can be changed into a prime (1020021511) 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, 543365 + ... + 545238.

It is an arithmetic number, because the mean of its divisors is an integer number (255277638).

Almost surely, 2^1020021011 is an apocalyptic number.

1020021011 is a deficient number, since it is larger than the sum of its proper divisors (1089541).

1020021011 is an equidigital number, since it uses as much as digits as its factorization.

1020021011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1089540.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1020021011 is about 31937.7677836132. The cubic root of 1020021011 is about 1006.6296213263.

Adding to 1020021011 its reverse (1101200201), we get a palindrome (2121221212).

The spelling of 1020021011 in words is "one billion, twenty million, twenty-one thousand, eleven".