77327521 has 4 divisors (see below), whose sum is σ = 79417492. Its totient is φ = 75237552.

The previous prime is 77327489. The next prime is 77327533. The reversal of 77327521 is 12572377.

It is a happy number.

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 71639296 + 5688225 = 8464^2 + 2385^2 .

It is a cyclic number.

It is not a de Polignac number, because 77327521 - 2⁵ = 77327489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77321521) 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, 1044930 + ... + 1045003.

It is an arithmetic number, because the mean of its divisors is an integer number (19854373).

Almost surely, 2^77327521 is an apocalyptic number.

It is an amenable number.

77327521 is a deficient number, since it is larger than the sum of its proper divisors (2089971).

77327521 is a wasteful number, since it uses less digits than its factorization.

77327521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2089970.

The product of its digits is 20580, while the sum is 34.

The square root of 77327521 is about 8793.6068254158. The cubic root of 77327521 is about 426.0344278494.

Adding to 77327521 its reverse (12572377), we get a palindrome (89899898).

The spelling of 77327521 in words is "seventy-seven million, three hundred twenty-seven thousand, five hundred twenty-one".