163253978209 has 27 divisors (see below), whose sum is σ = 191530260057. Its totient is φ = 138746507424.

The previous prime is 163253978143. The next prime is 163253978221. The reversal of 163253978209 is 902879352361.

The square root of 163253978209 is 404047.

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 141148235809 + 22105742400 = 375697^2 + 148680^2 .

It is not a de Polignac number, because 163253978209 - 2³⁵ = 128894239841 is a prime.

It is a super-2 number, since 2×163253978209² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 163253978209.

It is not an unprimeable number, because it can be changed into a prime (163253978249) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 557180667 + ... + 557180959.

Almost surely, 2^163253978209 is an apocalyptic number.

163253978209 is the 404047-th square number.

163253978209 is the 202024-th centered octagonal number.

It is an amenable number.

163253978209 is a deficient number, since it is larger than the sum of its proper divisors (28276281848).

163253978209 is an frugal number, since it uses more digits than its factorization.

163253978209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 994 (or 497 counting only the distinct ones).

The product of its (nonzero) digits is 4898880, while the sum is 55.

The spelling of 163253978209 in words is "one hundred sixty-three billion, two hundred fifty-three million, nine hundred seventy-eight thousand, two hundred nine".