77867840 has 56 divisors (see below), whose sum is σ = 189768480. Its totient is φ = 30417408.

The previous prime is 77867807. The next prime is 77867843. The reversal of 77867840 is 4876877.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77867843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10931 + ... + 16589.

Almost surely, 2^77867840 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 77867840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94884240).

77867840 is an abundant number, since it is smaller than the sum of its proper divisors (111900640).

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

77867840 is a wasteful number, since it uses less digits than its factorization.

77867840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5719 (or 5709 counting only the distinct ones).

The product of its (nonzero) digits is 526848, while the sum is 47.

The square root of 77867840 is about 8824.2756076632. The cubic root of 77867840 is about 427.0244178312.

The spelling of 77867840 in words is "seventy-seven million, eight hundred sixty-seven thousand, eight hundred forty".