64667680 has 192 divisors, whose sum is σ = 198132480. Its totient is φ = 19353600.

The previous prime is 64667653. The next prime is 64667689. The reversal of 64667680 is 8676646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64667689) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 357190 + ... + 357370.

It is an arithmetic number, because the mean of its divisors is an integer number (1031940).

Almost surely, 2^64667680 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 64667680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99066240).

64667680 is an abundant number, since it is smaller than the sum of its proper divisors (133464800).

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

64667680 is a wasteful number, since it uses less digits than its factorization.

64667680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243 (or 235 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 43.

The square root of 64667680 is about 8041.6217269901. The cubic root of 64667680 is about 401.3861906396.

The spelling of 64667680 in words is "sixty-four million, six hundred sixty-seven thousand, six hundred eighty".