4261165219081 has 27 divisors (see below), whose sum is σ = 4678489460757. Its totient is φ = 3880146357120.

The previous prime is 4261165219057. The next prime is 4261165219109. The reversal of 4261165219081 is 1809125611624.

The square root of 4261165219081 is 2064259.

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

It can be written as a sum of positive squares in 4 ways, for example, as 1477539922681 + 2783625296400 = 1215541^2 + 1668420^2 .

It is not a de Polignac number, because 4261165219081 - 2¹³ = 4261165210889 is a prime.

It is a super-2 number, since 2×4261165219081² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4261165219981) 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 26 ways as a sum of consecutive naturals, for example, 1087862535 + ... + 1087866451.

Almost surely, 2^{4261165219081} is an apocalyptic number.

4261165219081 is the 2064259-th square number.

4261165219081 is the 1032130-th centered octagonal number.

It is an amenable number.

4261165219081 is a deficient number, since it is larger than the sum of its proper divisors (417324241676).

4261165219081 is an frugal number, since it uses more digits than its factorization.

4261165219081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7930 (or 3965 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 46.

The spelling of 4261165219081 in words is "four trillion, two hundred sixty-one billion, one hundred sixty-five million, two hundred nineteen thousand, eighty-one".