261143445 has 8 divisors (see below), whose sum is σ = 417829536. Its totient is φ = 139276496.

The previous prime is 261143437. The next prime is 261143453. The reversal of 261143445 is 544341162.

It is an interprime number because it is at equal distance from previous prime (261143437) and next prime (261143453).

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

It is a cyclic number.

It is not a de Polignac number, because 261143445 - 2³ = 261143437 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8704767 + ... + 8704796.

It is an arithmetic number, because the mean of its divisors is an integer number (52228692).

Almost surely, 2^261143445 is an apocalyptic number.

It is an amenable number.

261143445 is a deficient number, since it is larger than the sum of its proper divisors (156686091).

261143445 is a wasteful number, since it uses less digits than its factorization.

261143445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17409571.

The product of its digits is 11520, while the sum is 30.

The square root of 261143445 is about 16159.9333228822. The cubic root of 261143445 is about 639.1847081024.

It can be divided in two parts, 2611 and 43445, that added together give a triangular number (46056 = T₃₀₃).

The spelling of 261143445 in words is "two hundred sixty-one million, one hundred forty-three thousand, four hundred forty-five".