68691636 has 36 divisors (see below), whose sum is σ = 186995172. Its totient is φ = 21135744.

The previous prime is 68691589. The next prime is 68691643. The reversal of 68691636 is 63619686.

68691636 is a `hidden beast` number, since 6 + 8 + 6 + 9 + 1 + 636 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 37822500 + 30869136 = 6150^2 + 5556^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 68691591 and 68691600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 72921 + ... + 73856.

Almost surely, 2^68691636 is an apocalyptic number.

It is an amenable number.

68691636 is an abundant number, since it is smaller than the sum of its proper divisors (118303536).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

68691636 is a wasteful number, since it uses less digits than its factorization.

68691636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146800 (or 146795 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 68691636 is about 8288.0417469991. The cubic root of 68691636 is about 409.5446779557.

The spelling of 68691636 in words is "sixty-eight million, six hundred ninety-one thousand, six hundred thirty-six".