77774440 has 16 divisors (see below), whose sum is σ = 174992580. Its totient is φ = 31109760.

The previous prime is 77774413. The next prime is 77774441. The reversal of 77774440 is 4447777.

It can be written as a sum of positive squares in 2 ways, for example, as 77193796 + 580644 = 8786^2 + 762^2 .

It is a Harshad number since it is a multiple of its sum of digits (40), and also a Moran number because the ratio is a prime number: 1944361 = 77774440 / (7 + 7 + 7 + 7 + 4 + 4 + 4 + 0).

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 77774393 and 77774402.

It is not an unprimeable number, because it can be changed into a prime (77774441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 972141 + ... + 972220.

Almost surely, 2^77774440 is an apocalyptic number.

It is an amenable number.

77774440 is an abundant number, since it is smaller than the sum of its proper divisors (97218140).

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

77774440 is a wasteful number, since it uses less digits than its factorization.

77774440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1944372 (or 1944368 counting only the distinct ones).

The product of its (nonzero) digits is 153664, while the sum is 40.

The square root of 77774440 is about 8818.9818006389. The cubic root of 77774440 is about 426.8536154485.

The spelling of 77774440 in words is "seventy-seven million, seven hundred seventy-four thousand, four hundred forty".