21130029 has 6 divisors (see below), whose sum is σ = 30521166. Its totient is φ = 14086680.

The previous prime is 21130027. The next prime is 21130037. The reversal of 21130029 is 92003112.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16281225 + 4848804 = 4035^2 + 2202^2 .

It is not a de Polignac number, because 21130029 - 2¹ = 21130027 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21129993 and 21130020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130027) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1173882 + ... + 1173899.

It is an arithmetic number, because the mean of its divisors is an integer number (5086861).

Almost surely, 2^21130029 is an apocalyptic number.

It is an amenable number.

21130029 is a deficient number, since it is larger than the sum of its proper divisors (9391137).

21130029 is a wasteful number, since it uses less digits than its factorization.

21130029 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2347787 (or 2347784 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 21130029 is about 4596.7411282342. The cubic root of 21130029 is about 276.4606752027.

The spelling of 21130029 in words is "twenty-one million, one hundred thirty thousand, twenty-nine".