143661261 has 16 divisors (see below), whose sum is σ = 201904640. Its totient is φ = 90609840.

The previous prime is 143661247. The next prime is 143661317. The reversal of 143661261 is 162166341.

It is not a de Polignac number, because 143661261 - 2¹⁴ = 143644877 is a prime.

It is a super-2 number, since 2×143661261² = 41277115824220242, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (143661211) 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, 59406 + ... + 61776.

It is an arithmetic number, because the mean of its divisors is an integer number (12619040).

Almost surely, 2^143661261 is an apocalyptic number.

It is an amenable number.

143661261 is a deficient number, since it is larger than the sum of its proper divisors (58243379).

143661261 is a wasteful number, since it uses less digits than its factorization.

143661261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3456.

The product of its digits is 5184, while the sum is 30.

The square root of 143661261 is about 11985.8775648677. The cubic root of 143661261 is about 523.7369620228.

The spelling of 143661261 in words is "one hundred forty-three million, six hundred sixty-one thousand, two hundred sixty-one".