43431859661 has 4 divisors (see below), whose sum is σ = 44832887424. Its totient is φ = 42030831900.

The previous prime is 43431859633. The next prime is 43431859753. The reversal of 43431859661 is 16695813434.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43431859661 is a prime.

It is a super-2 number, since 2×43431859661² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43431852661) 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, 700513835 + ... + 700513896.

It is an arithmetic number, because the mean of its divisors is an integer number (11208221856).

Almost surely, 2^43431859661 is an apocalyptic number.

It is an amenable number.

43431859661 is a deficient number, since it is larger than the sum of its proper divisors (1401027763).

43431859661 is a wasteful number, since it uses less digits than its factorization.

43431859661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1401027762.

The product of its digits is 1866240, while the sum is 50.

The spelling of 43431859661 in words is "forty-three billion, four hundred thirty-one million, eight hundred fifty-nine thousand, six hundred sixty-one".