1000021145 has 4 divisors (see below), whose sum is σ = 1200025380. Its totient is φ = 800016912.

The previous prime is 1000021133. The next prime is 1000021189. The reversal of 1000021145 is 5411200001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5411200001 = 3499 ⋅1546499.

It can be written as a sum of positive squares in 2 ways, for example, as 675012361 + 325008784 = 25981^2 + 18028^2 .

It is a cyclic number.

It is not a de Polignac number, because 1000021145 - 2⁶ = 1000021081 is a prime.

It is a super-2 number, since 2×1000021145² = 2000084580894222050, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100002110 + ... + 100002119.

It is an arithmetic number, because the mean of its divisors is an integer number (300006345).

Almost surely, 2^1000021145 is an apocalyptic number.

It is an amenable number.

1000021145 is a deficient number, since it is larger than the sum of its proper divisors (200004235).

1000021145 is an equidigital number, since it uses as much as digits as its factorization.

1000021145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200004234.

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 1000021145 is about 31623.1109317221. The cubic root of 1000021145 is about 1000.0070482837.

Adding to 1000021145 its reverse (5411200001), we get a palindrome (6411221146).

The spelling of 1000021145 in words is "one billion, twenty-one thousand, one hundred forty-five".