261145602 has 48 divisors (see below), whose sum is σ = 601375320. Its totient is φ = 81900288.

The previous prime is 261145589. The next prime is 261145613. The reversal of 261145602 is 206541162.

261145602 is a `hidden beast` number, since 2 + 6 + 11 + 45 + 602 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 253478241 + 7667361 = 15921^2 + 2769^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 86958 + ... + 89910.

Almost surely, 2^261145602 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261145602, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (300687660).

261145602 is an abundant number, since it is smaller than the sum of its proper divisors (340229718).

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

261145602 is a wasteful number, since it uses less digits than its factorization.

261145602 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3012 (or 2975 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 261145602 is about 16160.0000618812. Note that the first 4 decimals coincide. The cubic root of 261145602 is about 639.1864679495.

Adding to 261145602 its reverse (206541162), we get a palindrome (467686764).

The spelling of 261145602 in words is "two hundred sixty-one million, one hundred forty-five thousand, six hundred two".