261354 has 16 divisors (see below), whose sum is σ = 535392. Its totient is φ = 85008.

The previous prime is 261353. The next prime is 261379. The reversal of 261354 is 453162.

It is a happy number.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 261354.

It is not an unprimeable number, because it can be changed into a prime (261353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 249 + ... + 764.

It is an arithmetic number, because the mean of its divisors is an integer number (33462).

2²⁶¹³⁵⁴ is an apocalyptic number.

261354 is an abundant number, since it is smaller than the sum of its proper divisors (274038).

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

261354 is a wasteful number, since it uses less digits than its factorization.

261354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1061.

The product of its digits is 720, while the sum is 21.

The square root of 261354 is about 511.2279335091. The cubic root of 261354 is about 63.9356449450.

The spelling of 261354 in words is "two hundred sixty-one thousand, three hundred fifty-four".