261254549 has 2 divisors, whose sum is σ = 261254550. Its totient is φ = 261254548.

The previous prime is 261254519. The next prime is 261254557. The reversal of 261254549 is 945452162.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 175562500 + 85692049 = 13250^2 + 9257^2 .

It is a cyclic number.

It is not a de Polignac number, because 261254549 - 2¹² = 261250453 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261254509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130627274 + 130627275.

It is an arithmetic number, because the mean of its divisors is an integer number (130627275).

Almost surely, 2^261254549 is an apocalyptic number.

It is an amenable number.

261254549 is a deficient number, since it is larger than the sum of its proper divisors (1).

261254549 is an equidigital number, since it uses as much as digits as its factorization.

261254549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86400, while the sum is 38.

The square root of 261254549 is about 16163.3705952688. The cubic root of 261254549 is about 639.2753427201.

The spelling of 261254549 in words is "two hundred sixty-one million, two hundred fifty-four thousand, five hundred forty-nine".