66121334513156 has 24 divisors (see below), whose sum is σ = 124885961090520. Its totient is φ = 30450761010432.

The previous prime is 66121334513111. The next prime is 66121334513167. The reversal of 66121334513156 is 65131543312166.

It can be written as a sum of positive squares in 4 ways, for example, as 276061973056 + 65845272540100 = 525416^2 + 8114510^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66121334513156.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1391184251 + ... + 1391231778.

It is an arithmetic number, because the mean of its divisors is an integer number (5203581712105).

Almost surely, 2^{66121334513156} is an apocalyptic number.

It is an amenable number.

66121334513156 is a deficient number, since it is larger than the sum of its proper divisors (58764626577364).

66121334513156 is a wasteful number, since it uses less digits than its factorization.

66121334513156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2782416503 (or 2782416501 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 47.

The spelling of 66121334513156 in words is "sixty-six trillion, one hundred twenty-one billion, three hundred thirty-four million, five hundred thirteen thousand, one hundred fifty-six".