66440763 has 16 divisors (see below), whose sum is σ = 98560000. Its totient is φ = 44235720.

The previous prime is 66440761. The next prime is 66440771. The reversal of 66440763 is 36704466.

66440763 is a `hidden beast` number, since 6 + 644 + 0 + 7 + 6 + 3 = 666.

It is not a de Polignac number, because 66440763 - 2¹ = 66440761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66440761) 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, 32238 + ... + 34236.

It is an arithmetic number, because the mean of its divisors is an integer number (6160000).

Almost surely, 2^66440763 is an apocalyptic number.

66440763 is a deficient number, since it is larger than the sum of its proper divisors (32119237).

66440763 is a wasteful number, since it uses less digits than its factorization.

66440763 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3239 (or 3233 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 36.

The square root of 66440763 is about 8151.1203524424. The cubic root of 66440763 is about 405.0216175018.

The spelling of 66440763 in words is "sixty-six million, four hundred forty thousand, seven hundred sixty-three".