66720707071550 has 96 divisors (see below), whose sum is σ = 146735833305600. Its totient is φ = 22084444287360.

The previous prime is 66720707071547. The next prime is 66720707071589. The reversal of 66720707071550 is 5517070702766.

66720707071550 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-4 number, since 4×66720707071550⁴ (a number of 56 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66720707071492 and 66720707071501.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 93868391 + ... + 94576509.

It is an arithmetic number, because the mean of its divisors is an integer number (1528498263600).

Almost surely, 2^{66720707071550} is an apocalyptic number.

66720707071550 is an abundant number, since it is smaller than the sum of its proper divisors (80015126234050).

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

66720707071550 is a wasteful number, since it uses less digits than its factorization.

66720707071550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 717450 (or 717445 counting only the distinct ones).

The product of its (nonzero) digits is 4321800, while the sum is 53.

The spelling of 66720707071550 in words is "sixty-six trillion, seven hundred twenty billion, seven hundred seven million, seventy-one thousand, five hundred fifty".