195468781 has 2 divisors, whose sum is σ = 195468782. Its totient is φ = 195468780.

The previous prime is 195468773. The next prime is 195468799. The reversal of 195468781 is 187864591.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 131308681 + 64160100 = 11459^2 + 8010^2 .

It is an emirp because it is prime and its reverse (187864591) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 195468781 - 2³ = 195468773 is a prime.

It is a super-2 number, since 2×195468781² = 76416088691251922, which contains 22 as substring.

It is a zygodrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195468731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97734390 + 97734391.

It is an arithmetic number, because the mean of its divisors is an integer number (97734391).

Almost surely, 2^195468781 is an apocalyptic number.

195468781 is the 6253-rd centered decagonal number.

It is an amenable number.

195468781 is a deficient number, since it is larger than the sum of its proper divisors (1).

195468781 is an equidigital number, since it uses as much as digits as its factorization.

195468781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 483840, while the sum is 49.

The square root of 195468781 is about 13981.0150203767. The cubic root of 195468781 is about 580.3533132692.

It can be divided in two parts, 195468 and 781, that added together give a square (196249 = 443²).

The spelling of 195468781 in words is "one hundred ninety-five million, four hundred sixty-eight thousand, seven hundred eighty-one".