66310640 has 40 divisors (see below), whose sum is σ = 168190128. Its totient is φ = 24112640.

The previous prime is 66310639. The next prime is 66310649. The reversal of 66310640 is 4601366.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66310649) 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, 36797 + ... + 38556.

Almost surely, 2^66310640 is an apocalyptic number.

It is an amenable number.

66310640 is an abundant number, since it is smaller than the sum of its proper divisors (101879488).

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

66310640 is a wasteful number, since it uses less digits than its factorization.

66310640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75377 (or 75371 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 66310640 is about 8143.1345316162. The cubic root of 66310640 is about 404.7570355958.

The spelling of 66310640 in words is "sixty-six million, three hundred ten thousand, six hundred forty".