77999844 has 72 divisors (see below), whose sum is σ = 203927808. Its totient is φ = 23042880.

The previous prime is 77999839. The next prime is 77999849. The reversal of 77999844 is 44899977.

It is an interprime number because it is at equal distance from previous prime (77999839) and next prime (77999849).

It is not an unprimeable number, because it can be changed into a prime (77999849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 614109 + ... + 614235.

Almost surely, 2^77999844 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 77999844, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101963904).

77999844 is an abundant number, since it is smaller than the sum of its proper divisors (125927964).

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

77999844 is a wasteful number, since it uses less digits than its factorization.

77999844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305 (or 176 counting only the distinct ones).

The product of its digits is 4572288, while the sum is 57.

The square root of 77999844 is about 8831.7520345626. The cubic root of 77999844 is about 427.2655833257.

The spelling of 77999844 in words is "seventy-seven million, nine hundred ninety-nine thousand, eight hundred forty-four".