1165724881 has 2 divisors, whose sum is σ = 1165724882. Its totient is φ = 1165724880.

The previous prime is 1165724821. The next prime is 1165724887. The reversal of 1165724881 is 1884275611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 697435281 + 468289600 = 26409^2 + 21640^2 .

It is a cyclic number.

It is not a de Polignac number, because 1165724881 - 2²⁷ = 1031507153 is a prime.

It is a super-2 number, since 2×1165724881² = 2717828996364928322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1165724887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 582862440 + 582862441.

It is an arithmetic number, because the mean of its divisors is an integer number (582862441).

Almost surely, 2^1165724881 is an apocalyptic number.

It is an amenable number.

1165724881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1165724881 is an equidigital number, since it uses as much as digits as its factorization.

1165724881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 107520, while the sum is 43.

The square root of 1165724881 is about 34142.7134393270. The cubic root of 1165724881 is about 1052.4432539748.

The spelling of 1165724881 in words is "one billion, one hundred sixty-five million, seven hundred twenty-four thousand, eight hundred eighty-one".