77681238 has 8 divisors (see below), whose sum is σ = 155362488. Its totient is φ = 25893744.

The previous prime is 77681231. The next prime is 77681249. The reversal of 77681238 is 83218677.

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

77681238 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 77681238.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77681231) 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, 6473431 + ... + 6473442.

It is an arithmetic number, because the mean of its divisors is an integer number (19420311).

Almost surely, 2^77681238 is an apocalyptic number.

77681238 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77681238 is a wasteful number, since it uses less digits than its factorization.

77681238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12946878.

The product of its digits is 112896, while the sum is 42.

The square root of 77681238 is about 8813.6960464949. The cubic root of 77681238 is about 426.6830387869.

The spelling of 77681238 in words is "seventy-seven million, six hundred eighty-one thousand, two hundred thirty-eight".