261005090 has 32 divisors (see below), whose sum is σ = 499374720. Its totient is φ = 97939584.

The previous prime is 261004973. The next prime is 261005099. The reversal of 261005090 is 90500162.

It is not an unprimeable number, because it can be changed into a prime (261005099) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12902 + ... + 26238.

It is an arithmetic number, because the mean of its divisors is an integer number (15605460).

Almost surely, 2^261005090 is an apocalyptic number.

261005090 is a deficient number, since it is larger than the sum of its proper divisors (238369630).

261005090 is a wasteful number, since it uses less digits than its factorization.

261005090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13466.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 261005090 is about 16155.6519521807. The cubic root of 261005090 is about 639.0718071608.

The spelling of 261005090 in words is "two hundred sixty-one million, five thousand, ninety".