121602821 has 2 divisors, whose sum is σ = 121602822. Its totient is φ = 121602820.

The previous prime is 121602809. The next prime is 121602823. The reversal of 121602821 is 128206121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75498721 + 46104100 = 8689^2 + 6790^2 .

It is a cyclic number.

It is not a de Polignac number, because 121602821 - 2¹⁰ = 121601797 is a prime.

Together with 121602823, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121602823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60801410 + 60801411.

It is an arithmetic number, because the mean of its divisors is an integer number (60801411).

Almost surely, 2^121602821 is an apocalyptic number.

It is an amenable number.

121602821 is a deficient number, since it is larger than the sum of its proper divisors (1).

121602821 is an equidigital number, since it uses as much as digits as its factorization.

121602821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 121602821 is about 11027.3669114617. The cubic root of 121602821 is about 495.4287629456.

Adding to 121602821 its reverse (128206121), we get a palindrome (249808942).

The spelling of 121602821 in words is "one hundred twenty-one million, six hundred two thousand, eight hundred twenty-one".