66651750 has 96 divisors (see below), whose sum is σ = 196683552. Its totient is φ = 16152000.

The previous prime is 66651749. The next prime is 66651757. The reversal of 66651750 is 5715666.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66651757) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 23404 + ... + 26096.

It is an arithmetic number, because the mean of its divisors is an integer number (2048787).

Almost surely, 2^66651750 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66651750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98341776).

66651750 is an abundant number, since it is smaller than the sum of its proper divisors (130031802).

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

66651750 is a wasteful number, since it uses less digits than its factorization.

66651750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2727 (or 2714 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The square root of 66651750 is about 8164.0523026252. The cubic root of 66651750 is about 405.4498887225.

The spelling of 66651750 in words is "sixty-six million, six hundred fifty-one thousand, seven hundred fifty".