77943697 has 4 divisors (see below), whose sum is σ = 83939380. Its totient is φ = 71948016.

The previous prime is 77943689. The next prime is 77943709. The reversal of 77943697 is 79634977.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8737936 + 69205761 = 2956^2 + 8319^2 .

It is a cyclic number.

It is not a de Polignac number, because 77943697 - 2³ = 77943689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77943617) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2997822 + ... + 2997847.

It is an arithmetic number, because the mean of its divisors is an integer number (20984845).

Almost surely, 2^77943697 is an apocalyptic number.

It is an amenable number.

77943697 is a deficient number, since it is larger than the sum of its proper divisors (5995683).

77943697 is a wasteful number, since it uses less digits than its factorization.

77943697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5995682.

The product of its digits is 2000376, while the sum is 52.

The square root of 77943697 is about 8828.5727612112. The cubic root of 77943697 is about 427.1630385086.

The spelling of 77943697 in words is "seventy-seven million, nine hundred forty-three thousand, six hundred ninety-seven".