261544279396 has 27 divisors (see below), whose sum is σ = 470475236217. Its totient is φ = 127219346640.

The previous prime is 261544279379. The next prime is 261544279417. The reversal of 261544279396 is 693972445162.

The square root of 261544279396 is 511414.

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., 234033412900 + 27510866496 = 483770^2 + 165864^2 .

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors.

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 261544279396.

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, 37841181 + ... + 37848091.

Almost surely, 2^261544279396 is an apocalyptic number.

261544279396 is the 511414-th square number.

It is an amenable number.

261544279396 is a deficient number, since it is larger than the sum of its proper divisors (208930956821).

261544279396 is an frugal number, since it uses more digits than its factorization.

261544279396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13900 (or 6950 counting only the distinct ones).

The product of its digits is 19595520, while the sum is 58.

The spelling of 261544279396 in words is "two hundred sixty-one billion, five hundred forty-four million, two hundred seventy-nine thousand, three hundred ninety-six".