77971140 has 192 divisors, whose sum is σ = 270950400. Its totient is φ = 18482688.

The previous prime is 77971139. The next prime is 77971177. The reversal of 77971140 is 4117977.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 77971095 and 77971104.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 203389 + ... + 203771.

It is an arithmetic number, because the mean of its divisors is an integer number (1411200).

Almost surely, 2^77971140 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 77971140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135475200).

77971140 is an abundant number, since it is smaller than the sum of its proper divisors (192979260).

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

77971140 is a wasteful number, since it uses less digits than its factorization.

77971140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443 (or 435 counting only the distinct ones).

The product of its (nonzero) digits is 12348, while the sum is 36.

The square root of 77971140 is about 8830.1268394061. The cubic root of 77971140 is about 427.2131655455.

The spelling of 77971140 in words is "seventy-seven million, nine hundred seventy-one thousand, one hundred forty".