64868240 has 20 divisors (see below), whose sum is σ = 150818844. Its totient is φ = 25947264.

The previous prime is 64868239. The next prime is 64868249. The reversal of 64868240 is 4286846.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 28047616 + 36820624 = 5296^2 + 6068^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 64868194 and 64868203.

It is not an unprimeable number, because it can be changed into a prime (64868249) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 405347 + ... + 405506.

Almost surely, 2^64868240 is an apocalyptic number.

It is an amenable number.

64868240 is an abundant number, since it is smaller than the sum of its proper divisors (85950604).

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

64868240 is a wasteful number, since it uses less digits than its factorization.

64868240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 810866 (or 810860 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 38.

The square root of 64868240 is about 8054.0821947631. The cubic root of 64868240 is about 401.8007147350.

The spelling of 64868240 in words is "sixty-four million, eight hundred sixty-eight thousand, two hundred forty".