1166656721357 has 16 divisors (see below), whose sum is σ = 1202792572080. Its totient is φ = 1131100319232.

The previous prime is 1166656721333. The next prime is 1166656721383. The reversal of 1166656721357 is 7531276566611.

It can be written as a sum of positive squares in 8 ways, for example, as 283759701481 + 882897019876 = 532691^2 + 939626^2 .

It is a cyclic number.

It is not a de Polignac number, because 1166656721357 - 2¹⁴ = 1166656704973 is a prime.

It is a super-2 number, since 2×1166656721357² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1166656321357) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 1884113 + ... + 2425529.

It is an arithmetic number, because the mean of its divisors is an integer number (75174535755).

Almost surely, 2^{1166656721357} is an apocalyptic number.

It is an amenable number.

1166656721357 is a deficient number, since it is larger than the sum of its proper divisors (36135850723).

1166656721357 is a wasteful number, since it uses less digits than its factorization.

1166656721357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 541952.

The product of its digits is 9525600, while the sum is 56.

The spelling of 1166656721357 in words is "one trillion, one hundred sixty-six billion, six hundred fifty-six million, seven hundred twenty-one thousand, three hundred fifty-seven".