261948811 has 4 divisors (see below), whose sum is σ = 263396224. Its totient is φ = 260501400.

The previous prime is 261948773. The next prime is 261948821. The reversal of 261948811 is 118849162.

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 261948811 - 2⁷ = 261948683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261948821) 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, 723435 + ... + 723796.

It is an arithmetic number, because the mean of its divisors is an integer number (65849056).

Almost surely, 2^261948811 is an apocalyptic number.

261948811 is a deficient number, since it is larger than the sum of its proper divisors (1447413).

261948811 is a wasteful number, since it uses less digits than its factorization.

261948811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1447412.

The product of its digits is 27648, while the sum is 40.

The square root of 261948811 is about 16184.8327455059. The cubic root of 261948811 is about 639.8411153441.

The spelling of 261948811 in words is "two hundred sixty-one million, nine hundred forty-eight thousand, eight hundred eleven".