61231243511 has 4 divisors (see below), whose sum is σ = 61239533232. Its totient is φ = 61222953792.

The previous prime is 61231243487. The next prime is 61231243523. The reversal of 61231243511 is 11534213216.

61231243511 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.

It is a cyclic number.

It is not a de Polignac number, because 61231243511 - 2²² = 61227049207 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61231243531) 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, 4133771 + ... + 4148556.

It is an arithmetic number, because the mean of its divisors is an integer number (15309883308).

Almost surely, 2^61231243511 is an apocalyptic number.

61231243511 is a deficient number, since it is larger than the sum of its proper divisors (8289721).

61231243511 is an equidigital number, since it uses as much as digits as its factorization.

61231243511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8289720.

The product of its digits is 4320, while the sum is 29.

Adding to 61231243511 its reverse (11534213216), we get a palindrome (72765456727).

The spelling of 61231243511 in words is "sixty-one billion, two hundred thirty-one million, two hundred forty-three thousand, five hundred eleven".