121821331 has 16 divisors (see below), whose sum is σ = 131911200. Its totient is φ = 112147200.

The previous prime is 121821311. The next prime is 121821347. The reversal of 121821331 is 133128121.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 121821331 - 2⁹ = 121820819 is a prime.

It is a super-2 number, since 2×121821331² = 29680873373223122, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (121821311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 102561 + ... + 103741.

It is an arithmetic number, because the mean of its divisors is an integer number (8244450).

Almost surely, 2^121821331 is an apocalyptic number.

121821331 is a deficient number, since it is larger than the sum of its proper divisors (10089869).

121821331 is a wasteful number, since it uses less digits than its factorization.

121821331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350.

The product of its digits is 288, while the sum is 22.

The square root of 121821331 is about 11037.2700882057. The cubic root of 121821331 is about 495.7253332619.

Adding to 121821331 its reverse (133128121), we get a palindrome (254949452).

The spelling of 121821331 in words is "one hundred twenty-one million, eight hundred twenty-one thousand, three hundred thirty-one".