77671680 has 144 divisors (see below), whose sum is σ = 251657280. Its totient is φ = 20414464.

The previous prime is 77671679. The next prime is 77671681. The reversal of 77671680 is 8617677.

It is an interprime number because it is at equal distance from previous prime (77671679) and next prime (77671681).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77671681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 433831 + ... + 434009.

It is an arithmetic number, because the mean of its divisors is an integer number (1747620).

Almost surely, 2^77671680 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 77671680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125828640).

77671680 is an abundant number, since it is smaller than the sum of its proper divisors (173985600).

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

77671680 is a wasteful number, since it uses less digits than its factorization.

77671680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316 (or 302 counting only the distinct ones).

The product of its (nonzero) digits is 98784, while the sum is 42.

The square root of 77671680 is about 8813.1538055341. The cubic root of 77671680 is about 426.6655381915.

The spelling of 77671680 in words is "seventy-seven million, six hundred seventy-one thousand, six hundred eighty".