77887144 has 8 divisors (see below), whose sum is σ = 146038410. Its totient is φ = 38943568.

The previous prime is 77887141. The next prime is 77887163. The reversal of 77887144 is 44178877.

It can be written as a sum of positive squares in only one way, i.e., 50951044 + 26936100 = 7138^2 + 5190^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 77887094 and 77887103.

It is not an unprimeable number, because it can be changed into a prime (77887141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4867939 + ... + 4867954.

Almost surely, 2^77887144 is an apocalyptic number.

It is an amenable number.

77887144 is a deficient number, since it is larger than the sum of its proper divisors (68151266).

77887144 is a wasteful number, since it uses less digits than its factorization.

77887144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9735899 (or 9735895 counting only the distinct ones).

The product of its digits is 351232, while the sum is 46.

The square root of 77887144 is about 8825.3693407132. The cubic root of 77887144 is about 427.0597023948.

The spelling of 77887144 in words is "seventy-seven million, eight hundred eighty-seven thousand, one hundred forty-four".