66764560 has 40 divisors (see below), whose sum is σ = 155704320. Its totient is φ = 26623872.

The previous prime is 66764549. The next prime is 66764563. The reversal of 66764560 is 6546766.

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (66764563) 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, 29551 + ... + 31729.

It is an arithmetic number, because the mean of its divisors is an integer number (3892608).

Almost surely, 2^66764560 is an apocalyptic number.

It is an amenable number.

66764560 is an abundant number, since it is smaller than the sum of its proper divisors (88939760).

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

66764560 is a wasteful number, since it uses less digits than its factorization.

66764560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2575 (or 2569 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 40.

The square root of 66764560 is about 8170.9583281277. The cubic root of 66764560 is about 405.6785049826.

It can be divided in two parts, 6676 and 4560, that added together give a square (11236 = 106²).

The spelling of 66764560 in words is "sixty-six million, seven hundred sixty-four thousand, five hundred sixty".