65688493 has 8 divisors (see below), whose sum is σ = 74902968. Its totient is φ = 57068544.

The previous prime is 65688449. The next prime is 65688499. The reversal of 65688493 is 39488656.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 110889 + 65577604 = 333^2 + 8098^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 65688493 - 2⁹ = 65687981 is a prime.

It is a super-4 number, since 4×65688493⁴ (a number of 32 digits) contains 4444 as substring. Note that it is a super-d number also for d = 3, 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65688499) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 148396 + ... + 148837.

It is an arithmetic number, because the mean of its divisors is an integer number (9362871).

Almost surely, 2^65688493 is an apocalyptic number.

It is an amenable number.

65688493 is a deficient number, since it is larger than the sum of its proper divisors (9214475).

65688493 is a wasteful number, since it uses less digits than its factorization.

65688493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297263.

The product of its digits is 1244160, while the sum is 49.

The square root of 65688493 is about 8104.8437986182. The cubic root of 65688493 is about 403.4872039252.

The spelling of 65688493 in words is "sixty-five million, six hundred eighty-eight thousand, four hundred ninety-three".