77742180 has 120 divisors (see below), whose sum is σ = 250664568. Its totient is φ = 20155392.

The previous prime is 77742169. The next prime is 77742187. The reversal of 77742180 is 8124777.

It can be written as a sum of positive squares in 4 ways, for example, as 48776256 + 28965924 = 6984^2 + 5382^2 .

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

It is not an unprimeable number, because it can be changed into a prime (77742187) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 59292 + ... + 60588.

Almost surely, 2^77742180 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 77742180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125332284).

77742180 is an abundant number, since it is smaller than the sum of its proper divisors (172922388).

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

77742180 is a wasteful number, since it uses less digits than its factorization.

77742180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1355 (or 1344 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 36.

The square root of 77742180 is about 8817.1526016056. The cubic root of 77742180 is about 426.7945891926.

The spelling of 77742180 in words is "seventy-seven million, seven hundred forty-two thousand, one hundred eighty".