261421121132723 has 2 divisors, whose sum is σ = 261421121132724. Its totient is φ = 261421121132722.

The previous prime is 261421121132681. The next prime is 261421121132783. The reversal of 261421121132723 is 327231121124162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261421121132723 - 2²⁴ = 261421104355507 is a prime.

It is not a weakly prime, because it can be changed into another prime (261421121132783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130710560566361 + 130710560566362.

It is an arithmetic number, because the mean of its divisors is an integer number (130710560566362).

Almost surely, 2^{261421121132723} is an apocalyptic number.

261421121132723 is a deficient number, since it is larger than the sum of its proper divisors (1).

261421121132723 is an equidigital number, since it uses as much as digits as its factorization.

261421121132723 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 38.

Adding to 261421121132723 its reverse (327231121124162), we get a palindrome (588652242256885).

The spelling of 261421121132723 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, one hundred twenty-one million, one hundred thirty-two thousand, seven hundred twenty-three".