21130320043 has 16 divisors (see below), whose sum is σ = 24351275520. Its totient is φ = 17960155200.

The previous prime is 21130320007. The next prime is 21130320061. The reversal of 21130320043 is 34002303112.

It is a cyclic number.

It is not a de Polignac number, because 21130320043 - 2²¹ = 21128222891 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21130320043.

It is not an unprimeable number, because it can be changed into a prime (21130320143) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1350298 + ... + 1365856.

It is an arithmetic number, because the mean of its divisors is an integer number (1521954720).

Almost surely, 2^21130320043 is an apocalyptic number.

21130320043 is a deficient number, since it is larger than the sum of its proper divisors (3220955477).

21130320043 is a wasteful number, since it uses less digits than its factorization.

21130320043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17178.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 21130320043 its reverse (34002303112), we get a palindrome (55132623155).

The spelling of 21130320043 in words is "twenty-one billion, one hundred thirty million, three hundred twenty thousand, forty-three".