1000021001 has 4 divisors (see below), whose sum is σ = 1142881152. Its totient is φ = 857160852.

The previous prime is 1000020997. The next prime is 1000021003. The reversal of 1000021001 is 1001200001.

It is a happy number.

1000021001 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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: 1001200001 = 113 ⋅8860177.

It is a cyclic number.

It is not a de Polignac number, because 1000021001 - 2² = 1000020997 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1000021003) 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, 71430065 + ... + 71430078.

It is an arithmetic number, because the mean of its divisors is an integer number (285720288).

Almost surely, 2^1000021001 is an apocalyptic number.

It is an amenable number.

1000021001 is a deficient number, since it is larger than the sum of its proper divisors (142860151).

1000021001 is an equidigital number, since it uses as much as digits as its factorization.

1000021001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142860150.

The product of its (nonzero) digits is 2, while the sum is 5.

The square root of 1000021001 is about 31623.1086549061. The cubic root of 1000021001 is about 1000.0070002843.

Adding to 1000021001 its reverse (1001200001), we get a palindrome (2001221002).

The spelling of 1000021001 in words is "one billion, twenty-one thousand, one".