77780538 has 24 divisors (see below), whose sum is σ = 183845376. Its totient is φ = 23569800.

The previous prime is 77780513. The next prime is 77780539. The reversal of 77780538 is 83508777.

It is a junction number, because it is equal to n+sod(n) for n = 77780493 and 77780502.

It is not an unprimeable number, because it can be changed into a prime (77780539) 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 11 ways as a sum of consecutive naturals, for example, 196218 + ... + 196613.

It is an arithmetic number, because the mean of its divisors is an integer number (7660224).

Almost surely, 2^77780538 is an apocalyptic number.

77780538 is an abundant number, since it is smaller than the sum of its proper divisors (106064838).

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

77780538 is a wasteful number, since it uses less digits than its factorization.

77780538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392850 (or 392847 counting only the distinct ones).

The product of its (nonzero) digits is 329280, while the sum is 45.

The square root of 77780538 is about 8819.3275253842. The cubic root of 77780538 is about 426.8647711500.

The spelling of 77780538 in words is "seventy-seven million, seven hundred eighty thousand, five hundred thirty-eight".