1056991666201 has 3 divisors (see below), whose sum is σ = 1056992694303. Its totient is φ = 1056990638100.

The previous prime is 1056991666183. The next prime is 1056991666217. The reversal of 1056991666201 is 1026661996501.

It is a happy number.

The square root of 1056991666201 is 1028101.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 28917342601 + 1028074323600 = 170051^2 + 1013940^2 .

It is not a de Polignac number, because 1056991666201 - 2¹⁵ = 1056991633433 is a prime.

It is a super-2 number, since 2×1056991666201² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1056991666271) 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 2 ways as a sum of consecutive naturals, for example, 514051 + ... + 1542151.

It is an arithmetic number, because the mean of its divisors is an integer number (352330898101).

Almost surely, 2^{1056991666201} is an apocalyptic number.

1056991666201 is the 1028101-st square number.

1056991666201 is the 514051-st centered octagonal number.

It is an amenable number.

1056991666201 is a deficient number, since it is larger than the sum of its proper divisors (1028102).

1056991666201 is an frugal number, since it uses more digits than its factorization.

1056991666201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2056202 (or 1028101 counting only the distinct ones).

The product of its (nonzero) digits is 1049760, while the sum is 52.

The spelling of 1056991666201 in words is "one trillion, fifty-six billion, nine hundred ninety-one million, six hundred sixty-six thousand, two hundred one".