77781342573 has 18 divisors (see below), whose sum is σ = 123493060782. Its totient is φ = 47140206960.

The previous prime is 77781342571. The next prime is 77781342599. The reversal of 77781342573 is 37524318777.

77781342573 is a `hidden beast` number, since 7 + 77 + 81 + 3 + 425 + 73 = 666.

It can be written as a sum of positive squares in only one way, i.e., 67809722409 + 9971620164 = 260403^2 + 99858^2 .

It is not a de Polignac number, because 77781342573 - 2¹ = 77781342571 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77781342571) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 35711190 + ... + 35713367.

It is an arithmetic number, because the mean of its divisors is an integer number (6860725599).

Almost surely, 2^77781342573 is an apocalyptic number.

It is an amenable number.

77781342573 is a deficient number, since it is larger than the sum of its proper divisors (45711718209).

77781342573 is a wasteful number, since it uses less digits than its factorization.

77781342573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71424585 (or 71424571 counting only the distinct ones).

The product of its digits is 6914880, while the sum is 54.

The spelling of 77781342573 in words is "seventy-seven billion, seven hundred eighty-one million, three hundred forty-two thousand, five hundred seventy-three".