66670700813781 has 4 divisors (see below), whose sum is σ = 88894267751712. Its totient is φ = 44447133875852.

The previous prime is 66670700813767. The next prime is 66670700813867. The reversal of 66670700813781 is 18731800707666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66670700813781 - 2²⁹ = 66670163942869 is a prime.

It is a super-2 number, since 2×66670700813781² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66670700813081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11111783468961 + ... + 11111783468966.

It is an arithmetic number, because the mean of its divisors is an integer number (22223566937928).

Almost surely, 2^{66670700813781} is an apocalyptic number.

It is an amenable number.

66670700813781 is a deficient number, since it is larger than the sum of its proper divisors (22223566937931).

66670700813781 is a wasteful number, since it uses less digits than its factorization.

66670700813781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22223566937930.

The product of its (nonzero) digits is 14224896, while the sum is 60.

The spelling of 66670700813781 in words is "sixty-six trillion, six hundred seventy billion, seven hundred million, eight hundred thirteen thousand, seven hundred eighty-one".