64440280 has 32 divisors (see below), whose sum is σ = 145231200. Its totient is φ = 25733376.

The previous prime is 64440269. The next prime is 64440281. The reversal of 64440280 is 8204446.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64440281) 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, 35884 + ... + 37636.

It is an arithmetic number, because the mean of its divisors is an integer number (4538475).

Almost surely, 2^64440280 is an apocalyptic number.

It is an amenable number.

64440280 is an abundant number, since it is smaller than the sum of its proper divisors (80790920).

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

64440280 is a wasteful number, since it uses less digits than its factorization.

64440280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2683 (or 2679 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 28.

The square root of 64440280 is about 8027.4703362890. The cubic root of 64440280 is about 400.9151546332.

The spelling of 64440280 in words is "sixty-four million, four hundred forty thousand, two hundred eighty".