77839872 has 160 divisors (see below), whose sum is σ = 240413184. Its totient is φ = 22118400.

The previous prime is 77839871. The next prime is 77839873. The reversal of 77839872 is 27893877.

It is an interprime number because it is at equal distance from previous prime (77839871) and next prime (77839873).

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77839871) 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 15 ways as a sum of consecutive naturals, for example, 287097 + ... + 287367.

Almost surely, 2^77839872 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 77839872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120206592).

77839872 is an abundant number, since it is smaller than the sum of its proper divisors (162573312).

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

77839872 is a wasteful number, since it uses less digits than its factorization.

77839872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320 (or 304 counting only the distinct ones).

The product of its digits is 1185408, while the sum is 51.

The square root of 77839872 is about 8822.6907460253. The cubic root of 77839872 is about 426.9732865423.

The spelling of 77839872 in words is "seventy-seven million, eight hundred thirty-nine thousand, eight hundred seventy-two".