77172144 has 120 divisors (see below), whose sum is σ = 236413440. Its totient is φ = 21248640.

The previous prime is 77172089. The next prime is 77172149. The reversal of 77172144 is 44127177.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (77172149) 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, 322777 + ... + 323015.

It is an arithmetic number, because the mean of its divisors is an integer number (1970112).

Almost surely, 2^77172144 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 77172144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118206720).

77172144 is an abundant number, since it is smaller than the sum of its proper divisors (159241296).

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

77172144 is a wasteful number, since it uses less digits than its factorization.

77172144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319 (or 282 counting only the distinct ones).

The product of its digits is 10976, while the sum is 33.

The square root of 77172144 is about 8784.7677260130. The cubic root of 77172144 is about 425.7488876922.

The spelling of 77172144 in words is "seventy-seven million, one hundred seventy-two thousand, one hundred forty-four".