77999137 has 4 divisors (see below), whose sum is σ = 78276996. Its totient is φ = 77721280.

The previous prime is 77999087. The next prime is 77999143. The reversal of 77999137 is 73199977.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73199977 = 17 ⋅4305881.

It can be written as a sum of positive squares in 2 ways, for example, as 55711296 + 22287841 = 7464^2 + 4721^2 .

It is a cyclic number.

It is not a de Polignac number, because 77999137 - 2¹¹ = 77997089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77999197) 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, 138508 + ... + 139069.

It is an arithmetic number, because the mean of its divisors is an integer number (19569249).

Almost surely, 2^77999137 is an apocalyptic number.

It is an amenable number.

77999137 is a deficient number, since it is larger than the sum of its proper divisors (277859).

77999137 is a wasteful number, since it uses less digits than its factorization.

77999137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277858.

The product of its digits is 750141, while the sum is 52.

The square root of 77999137 is about 8831.7120084387. The cubic root of 77999137 is about 427.2642923929.

The spelling of 77999137 in words is "seventy-seven million, nine hundred ninety-nine thousand, one hundred thirty-seven".