121079821 has 2 divisors, whose sum is σ = 121079822. Its totient is φ = 121079820.

The previous prime is 121079801. The next prime is 121079887. The reversal of 121079821 is 128970121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64979721 + 56100100 = 8061^2 + 7490^2 .

It is a cyclic number.

It is not a de Polignac number, because 121079821 - 2¹⁵ = 121047053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121079801) 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 as a sum of consecutive naturals, namely, 60539910 + 60539911.

It is an arithmetic number, because the mean of its divisors is an integer number (60539911).

Almost surely, 2^121079821 is an apocalyptic number.

It is an amenable number.

121079821 is a deficient number, since it is larger than the sum of its proper divisors (1).

121079821 is an equidigital number, since it uses as much as digits as its factorization.

121079821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 121079821 is about 11003.6276291049. The cubic root of 121079821 is about 494.7174812019.

The spelling of 121079821 in words is "one hundred twenty-one million, seventy-nine thousand, eight hundred twenty-one".