21432221013 has 16 divisors (see below), whose sum is σ = 32673804416. Its totient is φ = 12241290240.

The previous prime is 21432221009. The next prime is 21432221021. The reversal of 21432221013 is 31012223412.

It is not a de Polignac number, because 21432221013 - 2² = 21432221009 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432221413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 190756 + ... + 281517.

It is an arithmetic number, because the mean of its divisors is an integer number (2042112776).

Almost surely, 2^21432221013 is an apocalyptic number.

It is an amenable number.

21432221013 is a deficient number, since it is larger than the sum of its proper divisors (11241583403).

21432221013 is a wasteful number, since it uses less digits than its factorization.

21432221013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474444.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21432221013 its reverse (31012223412), we get a palindrome (52444444425).

The spelling of 21432221013 in words is "twenty-one billion, four hundred thirty-two million, two hundred twenty-one thousand, thirteen".