77242745 has 4 divisors (see below), whose sum is σ = 92691300. Its totient is φ = 61794192.

The previous prime is 77242727. The next prime is 77242751. The reversal of 77242745 is 54724277.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54724277 = 521 ⋅105037.

It can be written as a sum of positive squares in 2 ways, for example, as 35200489 + 42042256 = 5933^2 + 6484^2 .

It is a cyclic number.

It is not a de Polignac number, because 77242745 - 2¹⁰ = 77241721 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 77242699 and 77242708.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 7724270 + ... + 7724279.

It is an arithmetic number, because the mean of its divisors is an integer number (23172825).

Almost surely, 2^77242745 is an apocalyptic number.

It is an amenable number.

77242745 is a deficient number, since it is larger than the sum of its proper divisors (15448555).

77242745 is a wasteful number, since it uses less digits than its factorization.

77242745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15448554.

The product of its digits is 109760, while the sum is 38.

The square root of 77242745 is about 8788.7851834028. The cubic root of 77242745 is about 425.8786803610.

The spelling of 77242745 in words is "seventy-seven million, two hundred forty-two thousand, seven hundred forty-five".