194990261 has 2 divisors, whose sum is σ = 194990262. Its totient is φ = 194990260.

The previous prime is 194990239. The next prime is 194990281. The reversal of 194990261 is 162099491.

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., 126000625 + 68989636 = 11225^2 + 8306^2 .

It is a cyclic number.

It is not a de Polignac number, because 194990261 - 2⁶ = 194990197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194990281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97495130 + 97495131.

It is an arithmetic number, because the mean of its divisors is an integer number (97495131).

Almost surely, 2^194990261 is an apocalyptic number.

It is an amenable number.

194990261 is a deficient number, since it is larger than the sum of its proper divisors (1).

194990261 is an equidigital number, since it uses as much as digits as its factorization.

194990261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 41.

The square root of 194990261 is about 13963.8913272769. The cubic root of 194990261 is about 579.8793456914.

The spelling of 194990261 in words is "one hundred ninety-four million, nine hundred ninety thousand, two hundred sixty-one".