1000002021 has 4 divisors (see below), whose sum is σ = 1333336032. Its totient is φ = 666668012.

The previous prime is 1000001969. The next prime is 1000002043. The reversal of 1000002021 is 1202000001.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1202000001 = 3 ⋅400666667.

It is a cyclic number.

It is not a de Polignac number, because 1000002021 - 2⁶ = 1000001957 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000002821) 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, 166667001 + ... + 166667006.

It is an arithmetic number, because the mean of its divisors is an integer number (333334008).

Almost surely, 2^1000002021 is an apocalyptic number.

It is an amenable number.

1000002021 is a deficient number, since it is larger than the sum of its proper divisors (333334011).

1000002021 is an equidigital number, since it uses as much as digits as its factorization.

1000002021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333334010.

The product of its (nonzero) digits is 4, while the sum is 6.

The square root of 1000002021 is about 31622.8085564834. The cubic root of 1000002021 is about 1000.0006736662. Note that the first 3 decimals are identical.

Adding to 1000002021 its reverse (1202000001), we get a palindrome (2202002022).

The spelling of 1000002021 in words is "one billion, two thousand, twenty-one".