209797893369 has 15 divisors (see below), whose sum is σ = 313407949503. Its totient is φ = 139862514024.

The previous prime is 209797893341. The next prime is 209797893373. The reversal of 209797893369 is 963398797902.

The square root of 209797893369 is 458037.

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

209797893369 is a `hidden beast` number, since 2 + 0 + 97 + 97 + 8 + 93 + 369 = 666.

It can be written as a sum of positive squares in only one way, i.e., 206066025 + 209591827344 = 14355^2 + 457812^2 .

It is not a de Polignac number, because 209797893369 - 2⁵ = 209797893337 is a prime.

It is a super-2 number, since 2×209797893369² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 209797893297 and 209797893306.

It is not an unprimeable number, because it can be changed into a prime (209797893329) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 4096887 + ... + 4147779.

Almost surely, 2^209797893369 is an apocalyptic number.

209797893369 is the 458037-th square number.

209797893369 is the 229019-th centered octagonal number.

It is an amenable number.

209797893369 is a deficient number, since it is larger than the sum of its proper divisors (103610056134).

209797893369 is an frugal number, since it uses more digits than its factorization.

209797893369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101798 (or 50896 counting only the distinct ones).

The product of its (nonzero) digits is 277766496, while the sum is 72.

The spelling of 209797893369 in words is "two hundred nine billion, seven hundred ninety-seven million, eight hundred ninety-three thousand, three hundred sixty-nine".