65648640 has 96 divisors (see below), whose sum is σ = 210122640. Its totient is φ = 17498112.

The previous prime is 65648633. The next prime is 65648657. The reversal of 65648640 is 4684656.

65648640 = T₃₈₁₅ + T₃₈₁₆ + ... + T₃₈₂₃.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29652 + ... + 31788.

Almost surely, 2^65648640 is an apocalyptic number.

65648640 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 65648640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105061320).

65648640 is an abundant number, since it is smaller than the sum of its proper divisors (144474000).

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

65648640 is a wasteful number, since it uses less digits than its factorization.

65648640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2167 (or 2147 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 39.

The square root of 65648640 is about 8102.3848341090. The cubic root of 65648640 is about 403.4055892829.

The spelling of 65648640 in words is "sixty-five million, six hundred forty-eight thousand, six hundred forty".