261315053 has 4 divisors (see below), whose sum is σ = 268377660. Its totient is φ = 254252448.

The previous prime is 261315049. The next prime is 261315083. The reversal of 261315053 is 350513162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 350513162 = 2 ⋅175256581.

It can be written as a sum of positive squares in 2 ways, for example, as 183927844 + 77387209 = 13562^2 + 8797^2 .

It is a cyclic number.

It is not a de Polignac number, because 261315053 - 2² = 261315049 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 (261315083) 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, 3531248 + ... + 3531321.

It is an arithmetic number, because the mean of its divisors is an integer number (67094415).

Almost surely, 2^261315053 is an apocalyptic number.

It is an amenable number.

261315053 is a deficient number, since it is larger than the sum of its proper divisors (7062607).

261315053 is an equidigital number, since it uses as much as digits as its factorization.

261315053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7062606.

The product of its (nonzero) digits is 2700, while the sum is 26.

The square root of 261315053 is about 16165.2421262411. The cubic root of 261315053 is about 639.3246888846.

The spelling of 261315053 in words is "two hundred sixty-one million, three hundred fifteen thousand, fifty-three".