261267253 has 4 divisors (see below), whose sum is σ = 281364748. Its totient is φ = 241169760.

The previous prime is 261267241. The next prime is 261267257. The reversal of 261267253 is 352762162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 352762162 = 2 ⋅176381081.

It can be written as a sum of positive squares in 2 ways, for example, as 130347889 + 130919364 = 11417^2 + 11442^2 .

It is a de Polignac number, because none of the positive numbers 2^k-261267253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261267257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10048728 + ... + 10048753.

It is an arithmetic number, because the mean of its divisors is an integer number (70341187).

Almost surely, 2^261267253 is an apocalyptic number.

It is an amenable number.

261267253 is a deficient number, since it is larger than the sum of its proper divisors (20097495).

261267253 is a wasteful number, since it uses less digits than its factorization.

261267253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20097494.

The product of its digits is 30240, while the sum is 34.

The square root of 261267253 is about 16163.7635778305. The cubic root of 261267253 is about 639.2857045458.

The spelling of 261267253 in words is "two hundred sixty-one million, two hundred sixty-seven thousand, two hundred fifty-three".