1021001021 has 8 divisors (see below), whose sum is σ = 1032224088. Its totient is φ = 1009800000.

The previous prime is 1021000963. The next prime is 1021001029. The reversal of 1021001021 is 1201001201.

It can be written as a sum of positive squares in 4 ways, for example, as 740438521 + 280562500 = 27211^2 + 16750^2 .

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 1021001021 - 2¹⁴ = 1020984637 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021001029) 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, 98171 + ... + 108071.

It is an arithmetic number, because the mean of its divisors is an integer number (129028011).

Almost surely, 2^1021001021 is an apocalyptic number.

It is an amenable number.

1021001021 is a deficient number, since it is larger than the sum of its proper divisors (11223067).

1021001021 is a wasteful number, since it uses less digits than its factorization.

1021001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11023.

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

The square root of 1021001021 is about 31953.1065938822. The cubic root of 1021001021 is about 1006.9518994350.

Adding to 1021001021 its reverse (1201001201), we get a palindrome (2222002222).

It can be divided in two parts, 102100 and 1021, that multiplied together give a square (104244100 = 10210²).

The spelling of 1021001021 in words is "one billion, twenty-one million, one thousand, twenty-one".