43729215661 has 8 divisors (see below), whose sum is σ = 43772022080. Its totient is φ = 43686433728.

The previous prime is 43729215659. The next prime is 43729215667. The reversal of 43729215661 is 16651292734.

It is a happy number.

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 43729215661 - 2¹ = 43729215659 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 (43729215667) 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, 6193045 + ... + 6200101.

It is an arithmetic number, because the mean of its divisors is an integer number (5471502760).

Almost surely, 2^43729215661 is an apocalyptic number.

It is an amenable number.

43729215661 is a deficient number, since it is larger than the sum of its proper divisors (42806419).

43729215661 is a wasteful number, since it uses less digits than its factorization.

43729215661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12243.

The product of its digits is 544320, while the sum is 46.

The spelling of 43729215661 in words is "forty-three billion, seven hundred twenty-nine million, two hundred fifteen thousand, six hundred sixty-one".