77693557 has 2 divisors, whose sum is σ = 77693558. Its totient is φ = 77693556.

The previous prime is 77693549. The next prime is 77693579. The reversal of 77693557 is 75539677.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62631396 + 15062161 = 7914^2 + 3881^2 .

It is an emirp because it is prime and its reverse (75539677) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77693557 - 2³ = 77693549 is a prime.

It is a super-3 number, since 3×77693557³ (a number of 25 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 77693557.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77693857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38846778 + 38846779.

It is an arithmetic number, because the mean of its divisors is an integer number (38846779).

Almost surely, 2^77693557 is an apocalyptic number.

It is an amenable number.

77693557 is a deficient number, since it is larger than the sum of its proper divisors (1).

77693557 is an equidigital number, since it uses as much as digits as its factorization.

77693557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1389150, while the sum is 49.

The square root of 77693557 is about 8814.3948742951. The cubic root of 77693557 is about 426.7055926264.

The spelling of 77693557 in words is "seventy-seven million, six hundred ninety-three thousand, five hundred fifty-seven".