21130043 has 4 divisors (see below), whose sum is σ = 23050968. Its totient is φ = 19209120.

The previous prime is 21130037. The next prime is 21130049. The reversal of 21130043 is 34003112.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21130037) and next prime (21130049).

It is a cyclic number.

It is not a de Polignac number, because 21130043 - 2⁴ = 21130027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21130049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 960446 + ... + 960467.

It is an arithmetic number, because the mean of its divisors is an integer number (5762742).

Almost surely, 2^21130043 is an apocalyptic number.

21130043 is a deficient number, since it is larger than the sum of its proper divisors (1920925).

21130043 is a wasteful number, since it uses less digits than its factorization.

21130043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1920924.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21130043 is about 4596.7426510519. The cubic root of 21130043 is about 276.4607362603.

Adding to 21130043 its reverse (34003112), we get a palindrome (55133155).

The spelling of 21130043 in words is "twenty-one million, one hundred thirty thousand, forty-three".