261938485 has 4 divisors (see below), whose sum is σ = 314326188. Its totient is φ = 209550784.

The previous prime is 261938477. The next prime is 261938491. The reversal of 261938485 is 584839162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 584839162 = 2 ⋅292419581.

It can be written as a sum of positive squares in 2 ways, for example, as 122722084 + 139216401 = 11078^2 + 11799^2 .

It is a cyclic number.

It is not a de Polignac number, because 261938485 - 2³ = 261938477 is a prime.

It is a super-2 number, since 2×261938485² = 137223539848190450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26193844 + ... + 26193853.

It is an arithmetic number, because the mean of its divisors is an integer number (78581547).

Almost surely, 2^261938485 is an apocalyptic number.

It is an amenable number.

261938485 is a deficient number, since it is larger than the sum of its proper divisors (52387703).

261938485 is an equidigital number, since it uses as much as digits as its factorization.

261938485 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52387702.

The product of its digits is 414720, while the sum is 46.

The square root of 261938485 is about 16184.5137399923. The cubic root of 261938485 is about 639.8327077394.

The spelling of 261938485 in words is "two hundred sixty-one million, nine hundred thirty-eight thousand, four hundred eighty-five".