65138688 has 208 divisors, whose sum is σ = 209689600. Its totient is φ = 19906560.

The previous prime is 65138687. The next prime is 65138699. The reversal of 65138688 is 88683156.

It is a super-2 number, since 2×65138688² = 8486097348722688, which contains 22 as substring.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65138683) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2101233 + ... + 2101263.

Almost surely, 2^65138688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65138688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104844800).

65138688 is an abundant number, since it is smaller than the sum of its proper divisors (144550912).

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

65138688 is a wasteful number, since it uses less digits than its factorization.

65138688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83 (or 55 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 65138688 is about 8070.8542298817. The cubic root of 65138688 is about 402.3583349810.

The spelling of 65138688 in words is "sixty-five million, one hundred thirty-eight thousand, six hundred eighty-eight".