43071643661 has 2 divisors, whose sum is σ = 43071643662. Its totient is φ = 43071643660.

The previous prime is 43071643619. The next prime is 43071643679. The reversal of 43071643661 is 16634617034.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23166666436 + 19904977225 = 152206^2 + 141085^2 .

It is a cyclic number.

It is not a de Polignac number, because 43071643661 - 2⁶ = 43071643597 is a prime.

It is a super-2 number, since 2×43071643661² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43071643061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21535821830 + 21535821831.

It is an arithmetic number, because the mean of its divisors is an integer number (21535821831).

Almost surely, 2^43071643661 is an apocalyptic number.

It is an amenable number.

43071643661 is a deficient number, since it is larger than the sum of its proper divisors (1).

43071643661 is an equidigital number, since it uses as much as digits as its factorization.

43071643661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 217728, while the sum is 41.

The spelling of 43071643661 in words is "forty-three billion, seventy-one million, six hundred forty-three thousand, six hundred sixty-one".