261123407 has 2 divisors, whose sum is σ = 261123408. Its totient is φ = 261123406.

The previous prime is 261123367. The next prime is 261123427. The reversal of 261123407 is 704321162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261123407 - 2⁸ = 261123151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261123427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130561703 + 130561704.

It is an arithmetic number, because the mean of its divisors is an integer number (130561704).

Almost surely, 2^261123407 is an apocalyptic number.

261123407 is a deficient number, since it is larger than the sum of its proper divisors (1).

261123407 is an equidigital number, since it uses as much as digits as its factorization.

261123407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 261123407 is about 16159.3133208067. The cubic root of 261123407 is about 639.1683590919.

Adding to 261123407 its reverse (704321162), we get a palindrome (965444569).

The spelling of 261123407 in words is "two hundred sixty-one million, one hundred twenty-three thousand, four hundred seven".