66621496787712 has 108 divisors (see below), whose sum is σ = 194791639193424. Its totient is φ = 21894388561920.

The previous prime is 66621496787689. The next prime is 66621496787719. The reversal of 66621496787712 is 21778769412666.

It is a super-3 number, since 3×66621496787712³ (a number of 42 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (66621496787719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 203467263 + ... + 203794430.

It is an arithmetic number, because the mean of its divisors is an integer number (1803626288828).

Almost surely, 2^{66621496787712} is an apocalyptic number.

It is an amenable number.

66621496787712 is an abundant number, since it is smaller than the sum of its proper divisors (128170142405712).

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

66621496787712 is a wasteful number, since it uses less digits than its factorization.

66621496787712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407261786 (or 407261769 counting only the distinct ones).

The product of its digits is 512096256, while the sum is 72.

The spelling of 66621496787712 in words is "sixty-six trillion, six hundred twenty-one billion, four hundred ninety-six million, seven hundred eighty-seven thousand, seven hundred twelve".