130000021 has 4 divisors (see below), whose sum is σ = 130122700. Its totient is φ = 129877344.

The previous prime is 130000009. The next prime is 130000027. The reversal of 130000021 is 120000031.

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 19980900 + 110019121 = 4470^2 + 10489^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-130000021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 129999959 and 130000013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (130000027) 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 3 ways as a sum of consecutive naturals, for example, 59736 + ... + 61873.

It is an arithmetic number, because the mean of its divisors is an integer number (32530675).

Almost surely, 2^130000021 is an apocalyptic number.

It is an amenable number.

130000021 is a deficient number, since it is larger than the sum of its proper divisors (122679).

130000021 is a wasteful number, since it uses less digits than its factorization.

130000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122678.

The product of its (nonzero) digits is 6, while the sum is 7.

The square root of 130000021 is about 11401.7551719023. The cubic root of 130000021 is about 506.5797291875.

Adding to 130000021 its reverse (120000031), we get a palindrome (250000052).

The spelling of 130000021 in words is "one hundred thirty million, twenty-one", and thus it is an aban number.