1161770721 has 4 divisors (see below), whose sum is σ = 1549027632. Its totient is φ = 774513812.

The previous prime is 1161770707. The next prime is 1161770773. The reversal of 1161770721 is 1270771611.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1270771611 = 3 ⋅423590537.

It is a cyclic number.

It is not a de Polignac number, because 1161770721 - 2¹³ = 1161762529 is a prime.

It is a super-2 number, since 2×1161770721² = 2699422416345719682, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1161770521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 193628451 + ... + 193628456.

It is an arithmetic number, because the mean of its divisors is an integer number (387256908).

Almost surely, 2^1161770721 is an apocalyptic number.

It is an amenable number.

1161770721 is a deficient number, since it is larger than the sum of its proper divisors (387256911).

1161770721 is an equidigital number, since it uses as much as digits as its factorization.

1161770721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387256910.

The product of its (nonzero) digits is 4116, while the sum is 33.

The square root of 1161770721 is about 34084.7578985094. The cubic root of 1161770721 is about 1051.2519370813.

The spelling of 1161770721 in words is "one billion, one hundred sixty-one million, seven hundred seventy thousand, seven hundred twenty-one".