1155764261 has 4 divisors (see below), whose sum is σ = 1223750412. Its totient is φ = 1087778112.

The previous prime is 1155764257. The next prime is 1155764279. The reversal of 1155764261 is 1624675511.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 911436100 + 244328161 = 30190^2 + 15631^2 .

It is a cyclic number.

It is not a de Polignac number, because 1155764261 - 2² = 1155764257 is a prime.

It is a super-2 number, since 2×1155764261² = 2671582054009752242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1155764161) 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, 33993050 + ... + 33993083.

It is an arithmetic number, because the mean of its divisors is an integer number (305937603).

Almost surely, 2^1155764261 is an apocalyptic number.

It is an amenable number.

1155764261 is a deficient number, since it is larger than the sum of its proper divisors (67986151).

1155764261 is an equidigital number, since it uses as much as digits as its factorization.

1155764261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67986150.

The product of its digits is 50400, while the sum is 38.

The square root of 1155764261 is about 33996.5330732415. The cubic root of 1155764261 is about 1049.4371165955.

The spelling of 1155764261 in words is "one billion, one hundred fifty-five million, seven hundred sixty-four thousand, two hundred sixty-one".