261543379 has 8 divisors (see below), whose sum is σ = 275729040. Its totient is φ = 247399776.

The previous prime is 261543377. The next prime is 261543389. The reversal of 261543379 is 973345162.

It is a happy number.

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 261543379 - 2¹ = 261543377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261543377) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2697 + ... + 23029.

It is an arithmetic number, because the mean of its divisors is an integer number (34466130).

Almost surely, 2^261543379 is an apocalyptic number.

261543379 is a deficient number, since it is larger than the sum of its proper divisors (14185661).

261543379 is a wasteful number, since it uses less digits than its factorization.

261543379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21029.

The product of its digits is 136080, while the sum is 40.

The square root of 261543379 is about 16172.3028354035. The cubic root of 261543379 is about 639.5108396024.

The spelling of 261543379 in words is "two hundred sixty-one million, five hundred forty-three thousand, three hundred seventy-nine".