120821761 has 8 divisors (see below), whose sum is σ = 124234920. Its totient is φ = 117416448.

The previous prime is 120821759. The next prime is 120821791. The reversal of 120821761 is 167128021.

It can be written as a sum of positive squares in 4 ways, for example, as 89113600 + 31708161 = 9440^2 + 5631^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 120821761 - 2¹ = 120821759 is a prime.

It is a super-2 number, since 2×120821761² = 29195795862282242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (120821791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44145 + ... + 46801.

It is an arithmetic number, because the mean of its divisors is an integer number (15529365).

Almost surely, 2^120821761 is an apocalyptic number.

It is an amenable number.

120821761 is a deficient number, since it is larger than the sum of its proper divisors (3413159).

120821761 is a wasteful number, since it uses less digits than its factorization.

120821761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3923.

The product of its (nonzero) digits is 1344, while the sum is 28.

The square root of 120821761 is about 10991.8952414950. The cubic root of 120821761 is about 494.3657639096.

Adding to 120821761 its reverse (167128021), we get a palindrome (287949782).

The spelling of 120821761 in words is "one hundred twenty million, eight hundred twenty-one thousand, seven hundred sixty-one".