688136537 has 4 divisors (see below), whose sum is σ = 750694416. Its totient is φ = 625578660.

The previous prime is 688136521. The next prime is 688136567. The reversal of 688136537 is 735631886.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 688136537 - 2⁴ = 688136521 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 688136491 and 688136500.

It is not an unprimeable number, because it can be changed into a prime (688136507) 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, 31278923 + ... + 31278944.

It is an arithmetic number, because the mean of its divisors is an integer number (187673604).

Almost surely, 2^688136537 is an apocalyptic number.

It is an amenable number.

688136537 is a deficient number, since it is larger than the sum of its proper divisors (62557879).

688136537 is a wasteful number, since it uses less digits than its factorization.

688136537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62557878.

The product of its digits is 725760, while the sum is 47.

The square root of 688136537 is about 26232.3566802527. The cubic root of 688136537 is about 882.8593873656.

The spelling of 688136537 in words is "six hundred eighty-eight million, one hundred thirty-six thousand, five hundred thirty-seven".