8161777156 has 12 divisors (see below), whose sum is σ = 15381810892. Its totient is φ = 3766974048.

The previous prime is 8161777093. The next prime is 8161777157. The reversal of 8161777156 is 6517771618.

It can be written as a sum of positive squares in 2 ways, for example, as 4682664900 + 3479112256 = 68430^2 + 58984^2 .

It is a super-2 number, since 2×8161777156² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (8161777157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78478575 + ... + 78478678.

Almost surely, 2^8161777156 is an apocalyptic number.

It is an amenable number.

8161777156 is a deficient number, since it is larger than the sum of its proper divisors (7220033736).

8161777156 is a wasteful number, since it uses less digits than its factorization.

8161777156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156957270 (or 156957268 counting only the distinct ones).

The product of its digits is 493920, while the sum is 49.

The square root of 8161777156 is about 90342.5545133632. The cubic root of 8161777156 is about 2013.3915625626.

The spelling of 8161777156 in words is "eight billion, one hundred sixty-one million, seven hundred seventy-seven thousand, one hundred fifty-six".