21130049 has 2 divisors, whose sum is σ = 21130050. Its totient is φ = 21130048.

The previous prime is 21130037. The next prime is 21130073. The reversal of 21130049 is 94003112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11937025 + 9193024 = 3455^2 + 3032^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21130049 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21130049.

It is not a weakly prime, because it can be changed into another prime (21130079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565024 + 10565025.

It is an arithmetic number, because the mean of its divisors is an integer number (10565025).

Almost surely, 2^21130049 is an apocalyptic number.

It is an amenable number.

21130049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21130049 is an equidigital number, since it uses as much as digits as its factorization.

21130049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 21130049 is about 4596.7433036879. The cubic root of 21130049 is about 276.4607624278.

The spelling of 21130049 in words is "twenty-one million, one hundred thirty thousand, forty-nine".