261393969 has 4 divisors (see below), whose sum is σ = 348525296. Its totient is φ = 174262644.

The previous prime is 261393961. The next prime is 261393971. The reversal of 261393969 is 969393162.

It is a happy number.

261393969 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 261393969 - 2³ = 261393961 is a prime.

It is a super-2 number, since 2×261393969² = 136653614059145922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261393961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43565659 + ... + 43565664.

It is an arithmetic number, because the mean of its divisors is an integer number (87131324).

Almost surely, 2^261393969 is an apocalyptic number.

It is an amenable number.

261393969 is a deficient number, since it is larger than the sum of its proper divisors (87131327).

261393969 is an equidigital number, since it uses as much as digits as its factorization.

261393969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87131326.

The product of its digits is 472392, while the sum is 48.

The square root of 261393969 is about 16167.6828580969. The cubic root of 261393969 is about 639.3890401578.

The spelling of 261393969 in words is "two hundred sixty-one million, three hundred ninety-three thousand, nine hundred sixty-nine".