1955108581 has 2 divisors, whose sum is σ = 1955108582. Its totient is φ = 1955108580.

The previous prime is 1955108521. The next prime is 1955108593. The reversal of 1955108581 is 1858015591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1919228481 + 35880100 = 43809^2 + 5990^2 .

It is an emirp because it is prime and its reverse (1858015591) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1955108581 - 2¹¹ = 1955106533 is a prime.

It is a super-4 number, since 4×1955108581⁴ (a number of 38 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1955108521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 977554290 + 977554291.

It is an arithmetic number, because the mean of its divisors is an integer number (977554291).

Almost surely, 2^1955108581 is an apocalyptic number.

It is an amenable number.

1955108581 is a deficient number, since it is larger than the sum of its proper divisors (1).

1955108581 is an equidigital number, since it uses as much as digits as its factorization.

1955108581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72000, while the sum is 43.

The square root of 1955108581 is about 44216.6097863687. The cubic root of 1955108581 is about 1250.4230207733.

The spelling of 1955108581 in words is "one billion, nine hundred fifty-five million, one hundred eight thousand, five hundred eighty-one".