77920189 has 4 divisors (see below), whose sum is σ = 78230880. Its totient is φ = 77609500.

The previous prime is 77920181. The next prime is 77920207. The reversal of 77920189 is 98102977.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 77920189 - 2³ = 77920181 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77920181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 154969 + ... + 155470.

It is an arithmetic number, because the mean of its divisors is an integer number (19557720).

Almost surely, 2^77920189 is an apocalyptic number.

It is an amenable number.

77920189 is a deficient number, since it is larger than the sum of its proper divisors (310691).

77920189 is a wasteful number, since it uses less digits than its factorization.

77920189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310690.

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 77920189 is about 8827.2413017885. The cubic root of 77920189 is about 427.1200897357.

The spelling of 77920189 in words is "seventy-seven million, nine hundred twenty thousand, one hundred eighty-nine".