194037581 has 2 divisors, whose sum is σ = 194037582. Its totient is φ = 194037580.

The previous prime is 194037563. The next prime is 194037619. The reversal of 194037581 is 185730491.

194037581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (194037619) can be obtained adding 194037581 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 187936681 + 6100900 = 13709^2 + 2470^2 .

It is a cyclic number.

It is not a de Polignac number, because 194037581 - 2⁶ = 194037517 is a prime.

It is a super-2 number, since 2×194037581² = 75301165680663122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194037551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97018790 + 97018791.

It is an arithmetic number, because the mean of its divisors is an integer number (97018791).

Almost surely, 2^194037581 is an apocalyptic number.

It is an amenable number.

194037581 is a deficient number, since it is larger than the sum of its proper divisors (1).

194037581 is an equidigital number, since it uses as much as digits as its factorization.

194037581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 194037581 is about 13929.7372911337. The cubic root of 194037581 is about 578.9334153632.

The spelling of 194037581 in words is "one hundred ninety-four million, thirty-seven thousand, five hundred eighty-one".