261630061 has 24 divisors (see below), whose sum is σ = 340139520. Its totient is φ = 198878400.

The previous prime is 261630053. The next prime is 261630073. The reversal of 261630061 is 160036162.

261630061 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 261630061 - 2³ = 261630053 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261630001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16180 + ... + 28018.

It is an arithmetic number, because the mean of its divisors is an integer number (14172480).

Almost surely, 2^261630061 is an apocalyptic number.

It is an amenable number.

261630061 is a deficient number, since it is larger than the sum of its proper divisors (78509459).

261630061 is a wasteful number, since it uses less digits than its factorization.

261630061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11905 (or 11898 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 261630061 is about 16174.9825656784. The cubic root of 261630061 is about 639.5814817471.

The spelling of 261630061 in words is "two hundred sixty-one million, six hundred thirty thousand, sixty-one".