77763561 has 16 divisors (see below), whose sum is σ = 111205440. Its totient is φ = 48185280.

The previous prime is 77763541. The next prime is 77763563. The reversal of 77763561 is 16536777.

It is not a de Polignac number, because 77763561 - 2¹¹ = 77761513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (77763563) 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 15 ways as a sum of consecutive naturals, for example, 9850 + ... + 15891.

It is an arithmetic number, because the mean of its divisors is an integer number (6950340).

Almost surely, 2^77763561 is an apocalyptic number.

It is an amenable number.

77763561 is a deficient number, since it is larger than the sum of its proper divisors (33441879).

77763561 is a wasteful number, since it uses less digits than its factorization.

77763561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25816.

The product of its digits is 185220, while the sum is 42.

The square root of 77763561 is about 8818.3649845082. The cubic root of 77763561 is about 426.8337119214.

The spelling of 77763561 in words is "seventy-seven million, seven hundred sixty-three thousand, five hundred sixty-one".