64415440 has 40 divisors (see below), whose sum is σ = 150256008. Its totient is φ = 25681920.

The previous prime is 64415423. The next prime is 64415443. The reversal of 64415440 is 4451446.

It can be written as a sum of positive squares in 4 ways, for example, as 6594624 + 57820816 = 2568^2 + 7604^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 64415399 and 64415408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64415443) 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, 27100 + ... + 29380.

Almost surely, 2^64415440 is an apocalyptic number.

It is an amenable number.

64415440 is an abundant number, since it is smaller than the sum of its proper divisors (85840568).

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

64415440 is a wasteful number, since it uses less digits than its factorization.

64415440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2647 (or 2641 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 28.

The square root of 64415440 is about 8025.9229998798. The cubic root of 64415440 is about 400.8636339988.

Adding to 64415440 its reverse (4451446), we get a palindrome (68866886).

It can be divided in two parts, 6441 and 5440, that added together give a square (11881 = 109²).

The spelling of 64415440 in words is "sixty-four million, four hundred fifteen thousand, four hundred forty".