77305520 has 20 divisors (see below), whose sum is σ = 179735520. Its totient is φ = 30922176.

The previous prime is 77305519. The next prime is 77305523. The reversal of 77305520 is 2550377.

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×77305520² = 11952286844940800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77305523) 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, 483080 + ... + 483239.

It is an arithmetic number, because the mean of its divisors is an integer number (8986776).

Almost surely, 2^77305520 is an apocalyptic number.

It is an amenable number.

77305520 is an abundant number, since it is smaller than the sum of its proper divisors (102430000).

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

77305520 is a wasteful number, since it uses less digits than its factorization.

77305520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 966332 (or 966326 counting only the distinct ones).

The product of its (nonzero) digits is 7350, while the sum is 29.

The square root of 77305520 is about 8792.3557707818. The cubic root of 77305520 is about 425.9940193272.

Adding to 77305520 its reverse (2550377), we get a palindrome (79855897).

The spelling of 77305520 in words is "seventy-seven million, three hundred five thousand, five hundred twenty".