64351440 has 120 divisors (see below), whose sum is σ = 218006880. Its totient is φ = 17010432.

The previous prime is 64351439. The next prime is 64351453. The reversal of 64351440 is 4415346.

64351440 is a `hidden beast` number, since 643 + 5 + 14 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×64351440² = 8282215660147200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 99759 + ... + 100401.

It is an arithmetic number, because the mean of its divisors is an integer number (1816724).

Almost surely, 2^64351440 is an apocalyptic number.

64351440 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 64351440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109003440).

64351440 is an abundant number, since it is smaller than the sum of its proper divisors (153655440).

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

64351440 is a wasteful number, since it uses less digits than its factorization.

64351440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801 (or 792 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 64351440 is about 8021.9349286815. The cubic root of 64351440 is about 400.7308305701.

Adding to 64351440 its reverse (4415346), we get a palindrome (68766786).

It can be divided in two parts, 6435 and 1440, that added together give a triangular number (7875 = T₁₂₅).

The spelling of 64351440 in words is "sixty-four million, three hundred fifty-one thousand, four hundred forty".