77872387 has 4 divisors (see below), whose sum is σ = 78432760. Its totient is φ = 77312016.

The previous prime is 77872381. The next prime is 77872439. The reversal of 77872387 is 78327877.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78327877 = 1051 ⋅74527.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77872387 is a prime.

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 77872387.

It is not an unprimeable number, because it can be changed into a prime (77872381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 279978 + ... + 280255.

It is an arithmetic number, because the mean of its divisors is an integer number (19608190).

Almost surely, 2^77872387 is an apocalyptic number.

77872387 is a deficient number, since it is larger than the sum of its proper divisors (560373).

77872387 is a wasteful number, since it uses less digits than its factorization.

77872387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560372.

The product of its digits is 921984, while the sum is 49.

The square root of 77872387 is about 8824.5332454470. The cubic root of 77872387 is about 427.0327295306.

The spelling of 77872387 in words is "seventy-seven million, eight hundred seventy-two thousand, three hundred eighty-seven".