1165784261 has 2 divisors, whose sum is σ = 1165784262. Its totient is φ = 1165784260.

The previous prime is 1165784227. The next prime is 1165784267. The reversal of 1165784261 is 1624875611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 670499236 + 495285025 = 25894^2 + 22255^2 .

It is a cyclic number.

It is not a de Polignac number, because 1165784261 - 2²⁶ = 1098675397 is a prime.

It is a super-2 number, since 2×1165784261² = 2718105886390632242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1165784267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 582892130 + 582892131.

It is an arithmetic number, because the mean of its divisors is an integer number (582892131).

Almost surely, 2^1165784261 is an apocalyptic number.

It is an amenable number.

1165784261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1165784261 is an equidigital number, since it uses as much as digits as its factorization.

1165784261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80640, while the sum is 41.

The square root of 1165784261 is about 34143.5830135034. The cubic root of 1165784261 is about 1052.4611235483.

The spelling of 1165784261 in words is "one billion, one hundred sixty-five million, seven hundred eighty-four thousand, two hundred sixty-one".