77997937 has 4 divisors (see below), whose sum is σ = 78279796. Its totient is φ = 77716080.

The previous prime is 77997929. The next prime is 77997943. The reversal of 77997937 is 73979977.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73979977 = 19 ⋅3893683.

It can be written as a sum of positive squares in 2 ways, for example, as 33362176 + 44635761 = 5776^2 + 6681^2 .

It is a cyclic number.

It is not a de Polignac number, because 77997937 - 2³ = 77997929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77997947) 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 in 3 ways as a sum of consecutive naturals, for example, 140514 + ... + 141067.

It is an arithmetic number, because the mean of its divisors is an integer number (19569949).

Almost surely, 2^77997937 is an apocalyptic number.

It is an amenable number.

77997937 is a deficient number, since it is larger than the sum of its proper divisors (281859).

77997937 is a wasteful number, since it uses less digits than its factorization.

77997937 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281858.

The product of its digits is 5250987, while the sum is 58.

The square root of 77997937 is about 8831.6440711795. The cubic root of 77997937 is about 427.2621012584.

The spelling of 77997937 in words is "seventy-seven million, nine hundred ninety-seven thousand, nine hundred thirty-seven".