64786440 has 64 divisors (see below), whose sum is σ = 195408000. Its totient is φ = 17183232.

The previous prime is 64786417. The next prime is 64786457. The reversal of 64786440 is 4468746.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22524 + ... + 25236.

It is an arithmetic number, because the mean of its divisors is an integer number (3053250).

Almost surely, 2^64786440 is an apocalyptic number.

64786440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64786440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97704000).

64786440 is an abundant number, since it is smaller than the sum of its proper divisors (130621560).

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

64786440 is a wasteful number, since it uses less digits than its factorization.

64786440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2926 (or 2922 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 39.

The square root of 64786440 is about 8049.0024226608. The cubic root of 64786440 is about 401.6317510862.

Subtracting from 64786440 its sum of digits (39), we obtain a square (64786401 = 8049²).

The spelling of 64786440 in words is "sixty-four million, seven hundred eighty-six thousand, four hundred forty".