193761989 has 4 divisors (see below), whose sum is σ = 195939180. Its totient is φ = 191584800.

The previous prime is 193761973. The next prime is 193761991. The reversal of 193761989 is 989167391.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23668225 + 170093764 = 4865^2 + 13042^2 .

It is a cyclic number.

It is not a de Polignac number, because 193761989 - 2⁴ = 193761973 is a prime.

It is a super-2 number, since 2×193761989² = 75087416762472242, which 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 193761989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (193761949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1088462 + ... + 1088639.

It is an arithmetic number, because the mean of its divisors is an integer number (48984795).

Almost surely, 2^193761989 is an apocalyptic number.

It is an amenable number.

193761989 is a deficient number, since it is larger than the sum of its proper divisors (2177191).

193761989 is an equidigital number, since it uses as much as digits as its factorization.

193761989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2177190.

The product of its digits is 734832, while the sum is 53.

The square root of 193761989 is about 13919.8415580063. The cubic root of 193761989 is about 578.6591987006.

The spelling of 193761989 in words is "one hundred ninety-three million, seven hundred sixty-one thousand, nine hundred eighty-nine".