77709889 has 4 divisors (see below), whose sum is σ = 77784880. Its totient is φ = 77634900.

The previous prime is 77709871. The next prime is 77709899. The reversal of 77709889 is 98890777.

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, and also an emirpimes, since its reverse is a distinct semiprime: 98890777 = 23 ⋅4299599.

It is a cyclic number.

It is not a de Polignac number, because 77709889 - 2¹¹ = 77707841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77709859) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35919 + ... + 38020.

It is an arithmetic number, because the mean of its divisors is an integer number (19446220).

Almost surely, 2^77709889 is an apocalyptic number.

It is an amenable number.

77709889 is a deficient number, since it is larger than the sum of its proper divisors (74991).

77709889 is a wasteful number, since it uses less digits than its factorization.

77709889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74990.

The product of its (nonzero) digits is 1778112, while the sum is 55.

The square root of 77709889 is about 8815.3212647073. The cubic root of 77709889 is about 426.7354898609.

The spelling of 77709889 in words is "seventy-seven million, seven hundred nine thousand, eight hundred eighty-nine".