261061011 has 24 divisors (see below), whose sum is σ = 393093584. Its totient is φ = 166795200.

The previous prime is 261061001. The next prime is 261061039. The reversal of 261061011 is 110160162.

261061011 = T₃₇₃₈ + T₃₇₃₉ + ... + T₃₇₇₄.

It is not a de Polignac number, because 261061011 - 2¹⁰ = 261059987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261061001) 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, 16461 + ... + 28161.

Almost surely, 2^261061011 is an apocalyptic number.

261061011 is a deficient number, since it is larger than the sum of its proper divisors (132032573).

261061011 is a wasteful number, since it uses less digits than its factorization.

261061011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11811 (or 11808 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 261061011 is about 16157.3825541144. The cubic root of 261061011 is about 639.1174448180.

The spelling of 261061011 in words is "two hundred sixty-one million, sixty-one thousand, eleven".