1002111021 has 10 divisors (see below), whose sum is σ = 1496980782. Its totient is φ = 668073960.

The previous prime is 1002111013. The next prime is 1002111029. The reversal of 1002111021 is 1201112001.

It is a happy number.

1002111021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1002111013) and next prime (1002111029).

It can be written as a sum of positive squares in only one way, i.e., 952956900 + 49154121 = 30870^2 + 7011^2 .

It is not a de Polignac number, because 1002111021 - 2³ = 1002111013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 1002110994 and 1002111012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1002111029) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 6185790 + ... + 6185951.

Almost surely, 2^1002111021 is an apocalyptic number.

It is an amenable number.

1002111021 is a deficient number, since it is larger than the sum of its proper divisors (494869761).

1002111021 is an equidigital number, since it uses as much as digits as its factorization.

1002111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12371753 (or 12371744 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 1002111021 is about 31656.1371774890. The cubic root of 1002111021 is about 1000.7031790899.

Adding to 1002111021 its reverse (1201112001), we get a palindrome (2203223022).

The spelling of 1002111021 in words is "one billion, two million, one hundred eleven thousand, twenty-one".