77531693 has 2 divisors, whose sum is σ = 77531694. Its totient is φ = 77531692.

The previous prime is 77531669. The next prime is 77531719. The reversal of 77531693 is 39613577.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54125449 + 23406244 = 7357^2 + 4838^2 .

It is an emirp because it is prime and its reverse (39613577) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77531693 - 2¹⁰ = 77530669 is a prime.

It is a super-2 number, since 2×77531693² = 12022326838892498, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 77531693.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77531393) 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 as a sum of consecutive naturals, namely, 38765846 + 38765847.

It is an arithmetic number, because the mean of its divisors is an integer number (38765847).

Almost surely, 2^77531693 is an apocalyptic number.

It is an amenable number.

77531693 is a deficient number, since it is larger than the sum of its proper divisors (1).

77531693 is an equidigital number, since it uses as much as digits as its factorization.

77531693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 119070, while the sum is 41.

The square root of 77531693 is about 8805.2082882803. The cubic root of 77531693 is about 426.4090588378.

The spelling of 77531693 in words is "seventy-seven million, five hundred thirty-one thousand, six hundred ninety-three".