1161628281 has 24 divisors (see below), whose sum is σ = 1836026400. Its totient is φ = 701870400.

The previous prime is 1161628201. The next prime is 1161628381. The reversal of 1161628281 is 1828261611.

1161628281 is a `hidden beast` number, since 1 + 1 + 6 + 1 + 628 + 28 + 1 = 666.

It is not a de Polignac number, because 1161628281 - 2²¹ = 1159531129 is a prime.

It is a super-2 number, since 2×1161628281² = 2698760526438029922, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1161628201) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15045 + ... + 50493.

It is an arithmetic number, because the mean of its divisors is an integer number (76501100).

Almost surely, 2^1161628281 is an apocalyptic number.

1161628281 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1161628281 is a deficient number, since it is larger than the sum of its proper divisors (674398119).

1161628281 is a wasteful number, since it uses less digits than its factorization.

1161628281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35797 (or 35794 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 1161628281 is about 34082.6683374410. The cubic root of 1161628281 is about 1051.2089720787.

Adding to 1161628281 its reverse (1828261611), we get a palindrome (2989889892).

The spelling of 1161628281 in words is "one billion, one hundred sixty-one million, six hundred twenty-eight thousand, two hundred eighty-one".