2130000021 has 6 divisors (see below), whose sum is σ = 3076666710. Its totient is φ = 1420000008.

The previous prime is 2130000017. The next prime is 2130000029. The reversal of 2130000021 is 1200000312.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1974024900 + 155975121 = 44430^2 + 12489^2 .

It is not a de Polignac number, because 2130000021 - 2² = 2130000017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 236666669 = 2130000021 / (2 + 1 + 3 + 0 + 0 + 0 + 0 + 0 + 2 + 1).

It is a junction number, because it is equal to n+sod(n) for n = 2129999958 and 2130000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2130000029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 118333326 + ... + 118333343.

It is an arithmetic number, because the mean of its divisors is an integer number (512777785).

Almost surely, 2^2130000021 is an apocalyptic number.

It is an amenable number.

2130000021 is a deficient number, since it is larger than the sum of its proper divisors (946666689).

2130000021 is a wasteful number, since it uses less digits than its factorization.

2130000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236666675 (or 236666672 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 2130000021 is about 46151.9232643668. The cubic root of 2130000021 is about 1286.6483554522.

Adding to 2130000021 its reverse (1200000312), we get a palindrome (3330000333).

The spelling of 2130000021 in words is "two billion, one hundred thirty million, twenty-one", and thus it is an aban number.