163693877281 has 9 divisors (see below), whose sum is σ = 179932872819. Its totient is φ = 148808569800.

The previous prime is 163693877261. The next prime is 163693877327. The reversal of 163693877281 is 182778396361.

The square root of 163693877281 is 404591.

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

It can be written as a sum of positive squares in only one way, i.e., 1075249681 + 162618627600 = 32791^2 + 403260^2 .

It is not a de Polignac number, because 163693877281 - 2⁷ = 163693877153 is a prime.

It is a super-2 number, since 2×163693877281² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (163693877201) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4432111 + ... + 4468891.

Almost surely, 2^163693877281 is an apocalyptic number.

163693877281 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

163693877281 is the 404591-st square number.

163693877281 is the 202296-th centered octagonal number.

It is an amenable number.

163693877281 is a deficient number, since it is larger than the sum of its proper divisors (16238995538).

163693877281 is an frugal number, since it uses more digits than its factorization.

163693877281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73584 (or 36792 counting only the distinct ones).

The product of its digits is 18289152, while the sum is 61.

The spelling of 163693877281 in words is "one hundred sixty-three billion, six hundred ninety-three million, eight hundred seventy-seven thousand, two hundred eighty-one".