21213404043 has 8 divisors (see below), whose sum is σ = 30460272528. Its totient is φ = 13054402464.

The previous prime is 21213404033. The next prime is 21213404063. The reversal of 21213404043 is 34040431212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21213404043 - 2⁹ = 21213403531 is a prime.

It is a super-2 number, since 2×21213404043² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21213404033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 271966680 + ... + 271966757.

It is an arithmetic number, because the mean of its divisors is an integer number (3807534066).

Almost surely, 2^21213404043 is an apocalyptic number.

21213404043 is a deficient number, since it is larger than the sum of its proper divisors (9246868485).

21213404043 is a wasteful number, since it uses less digits than its factorization.

21213404043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 543933453.

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21213404043 its reverse (34040431212), we get a palindrome (55253835255).

The spelling of 21213404043 in words is "twenty-one billion, two hundred thirteen million, four hundred four thousand, forty-three".