1000091021 has 8 divisors (see below), whose sum is σ = 1014942264. Its totient is φ = 985271040.

The previous prime is 1000091003. The next prime is 1000091039. The reversal of 1000091021 is 1201900001.

It is an interprime number because it is at equal distance from previous prime (1000091003) and next prime (1000091039).

It can be written as a sum of positive squares in 4 ways, for example, as 55204900 + 944886121 = 7430^2 + 30739^2 .

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 1000091021 - 2¹⁰ = 1000089997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1000090987 and 1000091005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000091321) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 61091 + ... + 75711.

It is an arithmetic number, because the mean of its divisors is an integer number (126867783).

Almost surely, 2^1000091021 is an apocalyptic number.

It is an amenable number.

1000091021 is a deficient number, since it is larger than the sum of its proper divisors (14851243).

1000091021 is an equidigital number, since it uses as much as digits as its factorization.

1000091021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15631.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 1000091021 is about 31624.2157373112. The cubic root of 1000091021 is about 1000.0303394128.

Adding to 1000091021 its reverse (1201900001), we get a palindrome (2201991022).

The spelling of 1000091021 in words is "one billion, ninety-one thousand, twenty-one".