261725620 has 24 divisors (see below), whose sum is σ = 591903144. Its totient is φ = 96637056.

The previous prime is 261725603. The next prime is 261725621. The reversal of 261725620 is 26527162.

It can be written as a sum of positive squares in 4 ways, for example, as 4892944 + 256832676 = 2212^2 + 16026^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261725621) 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 7 ways as a sum of consecutive naturals, for example, 503059 + ... + 503578.

It is an arithmetic number, because the mean of its divisors is an integer number (24662631).

Almost surely, 2^261725620 is an apocalyptic number.

261725620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261725620 is an abundant number, since it is smaller than the sum of its proper divisors (330177524).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261725620 is a wasteful number, since it uses less digits than its factorization.

261725620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1006659 (or 1006657 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 261725620 is about 16177.9362095417. The cubic root of 261725620 is about 639.6593401898.

The spelling of 261725620 in words is "two hundred sixty-one million, seven hundred twenty-five thousand, six hundred twenty".