65659440 has 480 divisors, whose sum is σ = 284981760. Its totient is φ = 12165120.

The previous prime is 65659439. The next prime is 65659463. The reversal of 65659440 is 4495656.

65659440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×65659440² = 8622324122227200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3455751 + ... + 3455769.

It is an arithmetic number, because the mean of its divisors is an integer number (593712).

Almost surely, 2^65659440 is an apocalyptic number.

65659440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65659440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142490880).

65659440 is an abundant number, since it is smaller than the sum of its proper divisors (219322320).

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

65659440 is a wasteful number, since it uses less digits than its factorization.

65659440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 39.

The square root of 65659440 is about 8103.0512771425. The cubic root of 65659440 is about 403.4277097791.

The spelling of 65659440 in words is "sixty-five million, six hundred fifty-nine thousand, four hundred forty".