195128395781 has 16 divisors (see below), whose sum is σ = 213432200640. Its totient is φ = 176919246720.

The previous prime is 195128395757. The next prime is 195128395783. The reversal of 195128395781 is 187593821591.

It is a cyclic number.

It is not a de Polignac number, because 195128395781 - 2¹⁸ = 195128133637 is a prime.

It is a super-2 number, since 2×195128395781² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 195128395781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195128395783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8232215 + ... + 8255883.

It is an arithmetic number, because the mean of its divisors is an integer number (13339512540).

Almost surely, 2^195128395781 is an apocalyptic number.

195128395781 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

195128395781 is a deficient number, since it is larger than the sum of its proper divisors (18303804859).

195128395781 is a wasteful number, since it uses less digits than its factorization.

195128395781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25636.

The product of its digits is 5443200, while the sum is 59.

The spelling of 195128395781 in words is "one hundred ninety-five billion, one hundred twenty-eight million, three hundred ninety-five thousand, seven hundred eighty-one".