65155001581 has 2 divisors, whose sum is σ = 65155001582. Its totient is φ = 65155001580.

The previous prime is 65155001551. The next prime is 65155001591. The reversal of 65155001581 is 18510055156.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38628364681 + 26526636900 = 196541^2 + 162870^2 .

It is a cyclic number.

It is not a de Polignac number, because 65155001581 - 2¹⁹ = 65154477293 is a prime.

It is a super-2 number, since 2×65155001581² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 65155001581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65155001501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32577500790 + 32577500791.

It is an arithmetic number, because the mean of its divisors is an integer number (32577500791).

Almost surely, 2^65155001581 is an apocalyptic number.

It is an amenable number.

65155001581 is a deficient number, since it is larger than the sum of its proper divisors (1).

65155001581 is an equidigital number, since it uses as much as digits as its factorization.

65155001581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30000, while the sum is 37.

The spelling of 65155001581 in words is "sixty-five billion, one hundred fifty-five million, one thousand, five hundred eighty-one".