261912249 has 12 divisors (see below), whose sum is σ = 380410212. Its totient is φ = 173642400.

The previous prime is 261912221. The next prime is 261912257. The reversal of 261912249 is 942219162.

261912249 is a `hidden beast` number, since 2 + 619 + 12 + 24 + 9 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 41835024 + 220077225 = 6468^2 + 14835^2 .

It is not a de Polignac number, because 261912249 - 2¹⁵ = 261879481 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (261912449) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 78762 + ... + 82019.

It is an arithmetic number, because the mean of its divisors is an integer number (31700851).

Almost surely, 2^261912249 is an apocalyptic number.

It is an amenable number.

261912249 is a deficient number, since it is larger than the sum of its proper divisors (118497963).

261912249 is a wasteful number, since it uses less digits than its factorization.

261912249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160968 (or 160965 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 261912249 is about 16183.7031917914. The cubic root of 261912249 is about 639.8113449483.

The spelling of 261912249 in words is "two hundred sixty-one million, nine hundred twelve thousand, two hundred forty-nine".