43434340021 has 8 divisors (see below), whose sum is σ = 44217966744. Its totient is φ = 42653022720.

The previous prime is 43434339973. The next prime is 43434340039. The reversal of 43434340021 is 12004343434.

It can be written as a sum of positive squares in 4 ways, for example, as 704902500 + 42729437521 = 26550^2 + 206711^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 43434340021 - 2²¹ = 43432242869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43434340091) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 539380 + ... + 614653.

It is an arithmetic number, because the mean of its divisors is an integer number (5527245843).

Almost surely, 2^43434340021 is an apocalyptic number.

It is an amenable number.

43434340021 is a deficient number, since it is larger than the sum of its proper divisors (783626723).

43434340021 is a wasteful number, since it uses less digits than its factorization.

43434340021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1154711.

The product of its (nonzero) digits is 13824, while the sum is 28.

Adding to 43434340021 its reverse (12004343434), we get a palindrome (55438683455).

The spelling of 43434340021 in words is "forty-three billion, four hundred thirty-four million, three hundred forty thousand, twenty-one".