77909887 has 8 divisors (see below), whose sum is σ = 85063680. Its totient is φ = 70767960.

The previous prime is 77909873. The next prime is 77909903. The reversal of 77909887 is 78890977.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77909887 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 (77909857) 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 7 ways as a sum of consecutive naturals, for example, 16164 + ... + 20422.

It is an arithmetic number, because the mean of its divisors is an integer number (10632960).

Almost surely, 2^77909887 is an apocalyptic number.

77909887 is a deficient number, since it is larger than the sum of its proper divisors (7153793).

77909887 is a wasteful number, since it uses less digits than its factorization.

77909887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5933.

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

The square root of 77909887 is about 8826.6577479814. The cubic root of 77909887 is about 427.1012654098.

The spelling of 77909887 in words is "seventy-seven million, nine hundred nine thousand, eight hundred eighty-seven".