77581116 has 72 divisors (see below), whose sum is σ = 209489280. Its totient is φ = 24149664.

The previous prime is 77581103. The next prime is 77581117. The reversal of 77581116 is 61118577.

It is a happy number.

77581116 is a `hidden beast` number, since 77 + 581 + 1 + 1 + 6 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77581117) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34515 + ... + 36693.

Almost surely, 2^77581116 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77581116, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104744640).

77581116 is an abundant number, since it is smaller than the sum of its proper divisors (131908164).

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

77581116 is a wasteful number, since it uses less digits than its factorization.

77581116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2255 (or 2250 counting only the distinct ones).

The product of its digits is 11760, while the sum is 36.

The square root of 77581116 is about 8808.0143051655. The cubic root of 77581116 is about 426.4996451846.

The spelling of 77581116 in words is "seventy-seven million, five hundred eighty-one thousand, one hundred sixteen".