195218761 has 2 divisors, whose sum is σ = 195218762. Its totient is φ = 195218760.

The previous prime is 195218747. The next prime is 195218791. The reversal of 195218761 is 167812591.

It is a happy number.

195218761 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 135001161 + 60217600 = 11619^2 + 7760^2 .

It is a cyclic number.

It is not a de Polignac number, because 195218761 - 2⁵ = 195218729 is a prime.

It is a super-2 number, since 2×195218761² = 76220729292750242, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (195218791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97609380 + 97609381.

It is an arithmetic number, because the mean of its divisors is an integer number (97609381).

Almost surely, 2^195218761 is an apocalyptic number.

195218761 is the 6249-th centered decagonal number.

It is an amenable number.

195218761 is a deficient number, since it is larger than the sum of its proper divisors (1).

195218761 is an equidigital number, since it uses as much as digits as its factorization.

195218761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 40.

The square root of 195218761 is about 13972.0707484610. The cubic root of 195218761 is about 580.1057684636.

It can be divided in two parts, 19521 and 8761, that added together give a palindrome (28282).

The spelling of 195218761 in words is "one hundred ninety-five million, two hundred eighteen thousand, seven hundred sixty-one".