41985311581 has 2 divisors, whose sum is σ = 41985311582. Its totient is φ = 41985311580.

The previous prime is 41985311479. The next prime is 41985311629. The reversal of 41985311581 is 18511358914.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27911048356 + 14074263225 = 167066^2 + 118635^2 .

It is a cyclic number.

It is not a de Polignac number, because 41985311581 - 2¹³ = 41985303389 is a prime.

It is a super-2 number, since 2×41985311581² (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 (41985611581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20992655790 + 20992655791.

It is an arithmetic number, because the mean of its divisors is an integer number (20992655791).

Almost surely, 2^41985311581 is an apocalyptic number.

It is an amenable number.

41985311581 is a deficient number, since it is larger than the sum of its proper divisors (1).

41985311581 is an equidigital number, since it uses as much as digits as its factorization.

41985311581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 172800, while the sum is 46.

The spelling of 41985311581 in words is "forty-one billion, nine hundred eighty-five million, three hundred eleven thousand, five hundred eighty-one".