77220385 has 12 divisors (see below), whose sum is σ = 101855124. Its totient is φ = 56159840.

The previous prime is 77220383. The next prime is 77220397. The reversal of 77220385 is 58302277.

It can be written as a sum of positive squares in 2 ways, for example, as 43996689 + 33223696 = 6633^2 + 5764^2 .

It is not a de Polignac number, because 77220385 - 2¹ = 77220383 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77220385.

It is not an unprimeable number, because it can be changed into a prime (77220383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63214 + ... + 64423.

It is an arithmetic number, because the mean of its divisors is an integer number (8487927).

Almost surely, 2^77220385 is an apocalyptic number.

It is an amenable number.

77220385 is a deficient number, since it is larger than the sum of its proper divisors (24634739).

77220385 is a wasteful number, since it uses less digits than its factorization.

77220385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127664 (or 127653 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 34.

The square root of 77220385 is about 8787.5130156376. The cubic root of 77220385 is about 425.8375823641.

The spelling of 77220385 in words is "seventy-seven million, two hundred twenty thousand, three hundred eighty-five".