64705840 has 40 divisors (see below), whose sum is σ = 153650880. Its totient is φ = 25330176.

The previous prime is 64705787. The next prime is 64705843. The reversal of 64705840 is 4850746.

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 = 64705796 and 64705805.

It is not an unprimeable number, because it can be changed into a prime (64705843) 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, 4845 + ... + 12364.

It is an arithmetic number, because the mean of its divisors is an integer number (3841272).

Almost surely, 2^64705840 is an apocalyptic number.

It is an amenable number.

64705840 is an abundant number, since it is smaller than the sum of its proper divisors (88945040).

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

64705840 is a wasteful number, since it uses less digits than its factorization.

64705840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17269 (or 17263 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 34.

The square root of 64705840 is about 8043.9940328173. The cubic root of 64705840 is about 401.4651269554.

The spelling of 64705840 in words is "sixty-four million, seven hundred five thousand, eight hundred forty".