261920484 has 108 divisors (see below), whose sum is σ = 791183484. Its totient is φ = 72793728.

The previous prime is 261920441. The next prime is 261920507. The reversal of 261920484 is 484029162.

It can be written as a sum of positive squares in 2 ways, for example, as 227346084 + 34574400 = 15078^2 + 5880^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 63262 + ... + 67274.

It is an arithmetic number, because the mean of its divisors is an integer number (7325773).

Almost surely, 2^261920484 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261920484, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395591742).

261920484 is an abundant number, since it is smaller than the sum of its proper divisors (529263000).

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

261920484 is a wasteful number, since it uses less digits than its factorization.

261920484 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4074 (or 4062 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 261920484 is about 16183.9576124012. The cubic root of 261920484 is about 639.8180504909.

The spelling of 261920484 in words is "two hundred sixty-one million, nine hundred twenty thousand, four hundred eighty-four".