66660225121505 has 16 divisors (see below), whose sum is σ = 81944293410000. Its totient is φ = 52026862755840.

The previous prime is 66660225121471. The next prime is 66660225121513. The reversal of 66660225121505 is 50512152206666.

It can be written as a sum of positive squares in 8 ways, for example, as 2814090304 + 66657411031201 = 53048^2 + 8164399^2 .

It is not a de Polignac number, because 66660225121505 - 2²⁰ = 66660224072929 is a prime.

It is a super-2 number, since 2×66660225121505² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66660225121505.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15373121 + ... + 19226369.

It is an arithmetic number, because the mean of its divisors is an integer number (5121518338125).

Almost surely, 2^{66660225121505} is an apocalyptic number.

It is an amenable number.

66660225121505 is a deficient number, since it is larger than the sum of its proper divisors (15284068288495).

66660225121505 is a wasteful number, since it uses less digits than its factorization.

66660225121505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3937684.

The product of its (nonzero) digits is 1296000, while the sum is 47.

The spelling of 66660225121505 in words is "sixty-six trillion, six hundred sixty billion, two hundred twenty-five million, one hundred twenty-one thousand, five hundred five".