21443430139 has 4 divisors (see below), whose sum is σ = 21445770400. Its totient is φ = 21441089880.

The previous prime is 21443430109. The next prime is 21443430163. The reversal of 21443430139 is 93103434412.

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

It is a cyclic number.

It is not a de Polignac number, because 21443430139 - 2¹⁷ = 21443299067 is a prime.

It is a super-2 number, since 2×21443430139² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21443430109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1156332 + ... + 1174729.

It is an arithmetic number, because the mean of its divisors is an integer number (5361442600).

Almost surely, 2^21443430139 is an apocalyptic number.

21443430139 is a deficient number, since it is larger than the sum of its proper divisors (2340261).

21443430139 is an equidigital number, since it uses as much as digits as its factorization.

21443430139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2340260.

The product of its (nonzero) digits is 31104, while the sum is 34.

The spelling of 21443430139 in words is "twenty-one billion, four hundred forty-three million, four hundred thirty thousand, one hundred thirty-nine".