77811982 has 8 divisors (see below), whose sum is σ = 117131256. Its totient is φ = 38768232.

The previous prime is 77811971. The next prime is 77811989. The reversal of 77811982 is 28911877.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77811989) 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, 68173 + ... + 69304.

It is an arithmetic number, because the mean of its divisors is an integer number (14641407).

Almost surely, 2^77811982 is an apocalyptic number.

77811982 is a deficient number, since it is larger than the sum of its proper divisors (39319274).

77811982 is a wasteful number, since it uses less digits than its factorization.

77811982 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137762.

The product of its digits is 56448, while the sum is 43.

The square root of 77811982 is about 8821.1100208534. The cubic root of 77811982 is about 426.9222856555.

The spelling of 77811982 in words is "seventy-seven million, eight hundred eleven thousand, nine hundred eighty-two".