43172760661 has 2 divisors, whose sum is σ = 43172760662. Its totient is φ = 43172760660.

The previous prime is 43172760649. The next prime is 43172760667. The reversal of 43172760661 is 16606727134.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42795196900 + 377563761 = 206870^2 + 19431^2 .

It is a cyclic number.

It is not a de Polignac number, because 43172760661 - 2¹¹ = 43172758613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43172760667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21586380330 + 21586380331.

It is an arithmetic number, because the mean of its divisors is an integer number (21586380331).

Almost surely, 2^43172760661 is an apocalyptic number.

It is an amenable number.

43172760661 is a deficient number, since it is larger than the sum of its proper divisors (1).

43172760661 is an equidigital number, since it uses as much as digits as its factorization.

43172760661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 254016, while the sum is 43.

The spelling of 43172760661 in words is "forty-three billion, one hundred seventy-two million, seven hundred sixty thousand, six hundred sixty-one".