1021121002009 has 4 divisors (see below), whose sum is σ = 1022820039220. Its totient is φ = 1019421964800.

The previous prime is 1021121002007. The next prime is 1021121002019. The reversal of 1021121002009 is 9002001211201.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 743388840000 + 277732162009 = 862200^2 + 527003^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021121002009 - 2¹ = 1021121002007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1021121002007) 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, 849517704 + ... + 849518905.

It is an arithmetic number, because the mean of its divisors is an integer number (255705009805).

Almost surely, 2^{1021121002009} is an apocalyptic number.

It is an amenable number.

1021121002009 is a deficient number, since it is larger than the sum of its proper divisors (1699037211).

1021121002009 is an equidigital number, since it uses as much as digits as its factorization.

1021121002009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1699037210.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 1021121002009 in words is "one trillion, twenty-one billion, one hundred twenty-one million, two thousand, nine".