261280819 has 8 divisors (see below), whose sum is σ = 262770272. Its totient is φ = 259796160.

The previous prime is 261280801. The next prime is 261280843. The reversal of 261280819 is 918082162.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261280819 is a prime.

It is a super-2 number, since 2×261280819² = 136535332754621522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261280919) 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, 168562 + ... + 170104.

It is an arithmetic number, because the mean of its divisors is an integer number (32846284).

Almost surely, 2^261280819 is an apocalyptic number.

261280819 is a deficient number, since it is larger than the sum of its proper divisors (1489453).

261280819 is a wasteful number, since it uses less digits than its factorization.

261280819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2397.

The product of its (nonzero) digits is 13824, while the sum is 37.

The square root of 261280819 is about 16164.1832147498. The cubic root of 261280819 is about 639.2967690780.

The spelling of 261280819 in words is "two hundred sixty-one million, two hundred eighty thousand, eight hundred nineteen".