77358521956 has 9 divisors (see below), whose sum is σ = 135378386899. Its totient is φ = 38678982844.

The previous prime is 77358521941. The next prime is 77358521957. The reversal of 77358521956 is 65912585377.

It is a happy number.

The square root of 77358521956 is 278134.

It is a perfect power (a square), and thus also a powerful number.

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 77358521956.

It is not an unprimeable number, because it can be changed into a prime (77358521957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 486735 + ... + 625801.

Almost surely, 2^77358521956 is an apocalyptic number.

77358521956 is the 278134-th square number.

It is an amenable number.

77358521956 is a deficient number, since it is larger than the sum of its proper divisors (58019864943).

77358521956 is an frugal number, since it uses more digits than its factorization.

77358521956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278138 (or 139069 counting only the distinct ones).

The product of its digits is 15876000, while the sum is 58.

The spelling of 77358521956 in words is "seventy-seven billion, three hundred fifty-eight million, five hundred twenty-one thousand, nine hundred fifty-six".