261543142 has 8 divisors (see below), whose sum is σ = 448359696. Its totient is φ = 112089912.

The previous prime is 261543103. The next prime is 261543169. The reversal of 261543142 is 241345162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 261543142.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9340813 + ... + 9340840.

It is an arithmetic number, because the mean of its divisors is an integer number (56044962).

Almost surely, 2^261543142 is an apocalyptic number.

261543142 is a deficient number, since it is larger than the sum of its proper divisors (186816554).

261543142 is a wasteful number, since it uses less digits than its factorization.

261543142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18681662.

The product of its digits is 5760, while the sum is 28.

The square root of 261543142 is about 16172.2955080595. The cubic root of 261543142 is about 639.5106464361.

It can be divided in two parts, 261 and 543142, that added together give a triangular number (543403 = T₁₀₄₂).

The spelling of 261543142 in words is "two hundred sixty-one million, five hundred forty-three thousand, one hundred forty-two".