66518691991131 has 8 divisors (see below), whose sum is σ = 88763754980880. Its totient is φ = 44309711831072.

The previous prime is 66518691991123. The next prime is 66518691991181. The reversal of 66518691991131 is 13119919681566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66518691991131 - 2³ = 66518691991123 is a prime.

It is a super-2 number, since 2×66518691991131² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66518691991181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9020703120 + ... + 9020710493.

It is an arithmetic number, because the mean of its divisors is an integer number (11095469372610).

Almost surely, 2^{66518691991131} is an apocalyptic number.

66518691991131 is a deficient number, since it is larger than the sum of its proper divisors (22245062989749).

66518691991131 is a wasteful number, since it uses less digits than its factorization.

66518691991131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18041414845.

The product of its digits is 18895680, while the sum is 66.

The spelling of 66518691991131 in words is "sixty-six trillion, five hundred eighteen billion, six hundred ninety-one million, nine hundred ninety-one thousand, one hundred thirty-one".