209774992144 has 45 divisors (see below), whose sum is σ = 412837409397. Its totient is φ = 103261553472.

The previous prime is 209774992139. The next prime is 209774992169. The reversal of 209774992144 is 441299477902.

The square root of 209774992144 is 458012.

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., 39437193744 + 170337798400 = 198588^2 + 412720^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 122746362 + ... + 122748070.

Almost surely, 2^209774992144 is an apocalyptic number.

209774992144 is the 458012-nd square number.

It is an amenable number.

209774992144 is a deficient number, since it is larger than the sum of its proper divisors (203062417253).

209774992144 is an frugal number, since it uses more digits than its factorization.

209774992144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3560 (or 1778 counting only the distinct ones).

The product of its (nonzero) digits is 9144576, while the sum is 58.

It can be divided in two parts, 20977 and 4992144, that added together give a square (5013121 = 2239²).

The spelling of 209774992144 in words is "two hundred nine billion, seven hundred seventy-four million, nine hundred ninety-two thousand, one hundred forty-four".