261254501 has 12 divisors (see below), whose sum is σ = 271322604. Its totient is φ = 251409600.

The previous prime is 261254473. The next prime is 261254509. The reversal of 261254501 is 105452162.

It can be written as a sum of positive squares in 2 ways, for example, as 70123876 + 191130625 = 8374^2 + 13825^2 .

It is not a de Polignac number, because 261254501 - 2¹⁸ = 260992357 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 (261254509) 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, 255371 + ... + 256391.

It is an arithmetic number, because the mean of its divisors is an integer number (22610217).

Almost surely, 2^261254501 is an apocalyptic number.

It is an amenable number.

261254501 is a deficient number, since it is larger than the sum of its proper divisors (10068103).

261254501 is an equidigital number, since it uses as much as digits as its factorization.

261254501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1220 (or 1141 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 261254501 is about 16163.3691104299. The cubic root of 261254501 is about 639.2753035690.

The spelling of 261254501 in words is "two hundred sixty-one million, two hundred fifty-four thousand, five hundred one".