64947680 has 96 divisors (see below), whose sum is σ = 177375744. Its totient is φ = 22012416.

The previous prime is 64947677. The next prime is 64947683. The reversal of 64947680 is 8674946.

It is an interprime number because it is at equal distance from previous prime (64947677) and next prime (64947683).

It is a super-2 number, since 2×64947680² = 8436402274764800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64947683) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115079 + ... + 115641.

It is an arithmetic number, because the mean of its divisors is an integer number (1847664).

Almost surely, 2^64947680 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 64947680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88687872).

64947680 is an abundant number, since it is smaller than the sum of its proper divisors (112428064).

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

64947680 is a wasteful number, since it uses less digits than its factorization.

64947680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688 (or 680 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 44.

The square root of 64947680 is about 8059.0123464355. The cubic root of 64947680 is about 401.9646677362.

The spelling of 64947680 in words is "sixty-four million, nine hundred forty-seven thousand, six hundred eighty".