261311433 has 8 divisors (see below), whose sum is σ = 349387200. Its totient is φ = 173721648.

The previous prime is 261311429. The next prime is 261311447. The reversal of 261311433 is 334113162.

It is a happy number.

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

It is not a de Polignac number, because 261311433 - 2² = 261311429 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261311933) 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, 120238 + ... + 122391.

It is an arithmetic number, because the mean of its divisors is an integer number (43673400).

Almost surely, 2^261311433 is an apocalyptic number.

It is an amenable number.

261311433 is a deficient number, since it is larger than the sum of its proper divisors (88075767).

261311433 is a wasteful number, since it uses less digits than its factorization.

261311433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242991.

The product of its digits is 1296, while the sum is 24.

The square root of 261311433 is about 16165.1301572242. The cubic root of 261311433 is about 639.3217366805.

Adding to 261311433 its reverse (334113162), we get a palindrome (595424595).

The spelling of 261311433 in words is "two hundred sixty-one million, three hundred eleven thousand, four hundred thirty-three".