261373811 has 4 divisors (see below), whose sum is σ = 267748824. Its totient is φ = 254998800.

The previous prime is 261373789. The next prime is 261373813. The reversal of 261373811 is 118373162.

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 261373811 - 2¹⁴ = 261357427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261373813) 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, 3187445 + ... + 3187526.

It is an arithmetic number, because the mean of its divisors is an integer number (66937206).

Almost surely, 2^261373811 is an apocalyptic number.

261373811 is a deficient number, since it is larger than the sum of its proper divisors (6375013).

261373811 is an equidigital number, since it uses as much as digits as its factorization.

261373811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6375012.

The product of its digits is 6048, while the sum is 32.

The square root of 261373811 is about 16167.0594419641. The cubic root of 261373811 is about 639.3726037475.

The spelling of 261373811 in words is "two hundred sixty-one million, three hundred seventy-three thousand, eight hundred eleven".