77281740 has 144 divisors (see below), whose sum is σ = 251596800. Its totient is φ = 19142784.

The previous prime is 77281733. The next prime is 77281741. The reversal of 77281740 is 4718277.

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 = 77281695 and 77281704.

It is not an unprimeable number, because it can be changed into a prime (77281741) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 201589 + ... + 201971.

It is an arithmetic number, because the mean of its divisors is an integer number (1747200).

Almost surely, 2^77281740 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 77281740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125798400).

77281740 is an abundant number, since it is smaller than the sum of its proper divisors (174315060).

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

77281740 is a wasteful number, since it uses less digits than its factorization.

77281740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 476 (or 471 counting only the distinct ones).

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

The square root of 77281740 is about 8791.0033557041. The cubic root of 77281740 is about 425.9503347509.

The spelling of 77281740 in words is "seventy-seven million, two hundred eighty-one thousand, seven hundred forty".