261373513 has 4 divisors (see below), whose sum is σ = 268437700. Its totient is φ = 254309328.

The previous prime is 261373459. The next prime is 261373529. The reversal of 261373513 is 315373162.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 221771664 + 39601849 = 14892^2 + 6293^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261373513 is a prime.

It is a super-2 number, since 2×261373513² = 136632226595922338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261373573) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3532038 + ... + 3532111.

It is an arithmetic number, because the mean of its divisors is an integer number (67109425).

Almost surely, 2^261373513 is an apocalyptic number.

It is an amenable number.

261373513 is a deficient number, since it is larger than the sum of its proper divisors (7064187).

261373513 is an equidigital number, since it uses as much as digits as its factorization.

261373513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7064186.

The product of its digits is 11340, while the sum is 31.

The square root of 261373513 is about 16167.0502256905. The cubic root of 261373513 is about 639.3723607582.

The spelling of 261373513 in words is "two hundred sixty-one million, three hundred seventy-three thousand, five hundred thirteen".