64442240 has 64 divisors (see below), whose sum is σ = 163146960. Its totient is φ = 24256512.

The previous prime is 64442239. The next prime is 64442267. The reversal of 64442240 is 4224446.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7919 + ... + 13841.

Almost surely, 2^64442240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64442240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81573480).

64442240 is an abundant number, since it is smaller than the sum of its proper divisors (98704720).

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

64442240 is a wasteful number, since it uses less digits than its factorization.

64442240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5959 (or 5947 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 26.

The square root of 64442240 is about 8027.5924161607. The cubic root of 64442240 is about 400.9192193049.

Adding to 64442240 its reverse (4224446), we get a palindrome (68666686).

The spelling of 64442240 in words is "sixty-four million, four hundred forty-two thousand, two hundred forty".