66815855534 has 16 divisors (see below), whose sum is σ = 102076058976. Its totient is φ = 32792752800.

The previous prime is 66815855527. The next prime is 66815855593. The reversal of 66815855534 is 43555851866.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 66815855534.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 502877 + ... + 621704.

It is an arithmetic number, because the mean of its divisors is an integer number (6379753686).

Almost surely, 2^66815855534 is an apocalyptic number.

66815855534 is a deficient number, since it is larger than the sum of its proper divisors (35260203442).

66815855534 is a wasteful number, since it uses less digits than its factorization.

66815855534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1125131.

The product of its digits is 17280000, while the sum is 56.

The spelling of 66815855534 in words is "sixty-six billion, eight hundred fifteen million, eight hundred fifty-five thousand, five hundred thirty-four".