66155515502 has 4 divisors (see below), whose sum is σ = 99233273256. Its totient is φ = 33077757750.

The previous prime is 66155515493. The next prime is 66155515571. The reversal of 66155515502 is 20551555166.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 66155515502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16538878874 + ... + 16538878877.

It is an arithmetic number, because the mean of its divisors is an integer number (24808318314).

Almost surely, 2^66155515502 is an apocalyptic number.

66155515502 is a deficient number, since it is larger than the sum of its proper divisors (33077757754).

66155515502 is a wasteful number, since it uses less digits than its factorization.

66155515502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33077757753.

The product of its (nonzero) digits is 225000, while the sum is 41.

The spelling of 66155515502 in words is "sixty-six billion, one hundred fifty-five million, five hundred fifteen thousand, five hundred two".