43554097781 has 2 divisors, whose sum is σ = 43554097782. Its totient is φ = 43554097780.

The previous prime is 43554097759. The next prime is 43554097831. The reversal of 43554097781 is 18779045534.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36582682756 + 6971415025 = 191266^2 + 83495^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43554097781 is a prime.

It is a super-2 number, since 2×43554097781² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43554097751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21777048890 + 21777048891.

It is an arithmetic number, because the mean of its divisors is an integer number (21777048891).

Almost surely, 2^43554097781 is an apocalyptic number.

It is an amenable number.

43554097781 is a deficient number, since it is larger than the sum of its proper divisors (1).

43554097781 is an equidigital number, since it uses as much as digits as its factorization.

43554097781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4233600, while the sum is 53.

The spelling of 43554097781 in words is "forty-three billion, five hundred fifty-four million, ninety-seven thousand, seven hundred eighty-one".