121398857 has 2 divisors, whose sum is σ = 121398858. Its totient is φ = 121398856.

The previous prime is 121398839. The next prime is 121398881. The reversal of 121398857 is 758893121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 115691536 + 5707321 = 10756^2 + 2389^2 .

It is a cyclic number.

It is not a de Polignac number, because 121398857 - 2¹² = 121394761 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (121398817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60699428 + 60699429.

It is an arithmetic number, because the mean of its divisors is an integer number (60699429).

Almost surely, 2^121398857 is an apocalyptic number.

It is an amenable number.

121398857 is a deficient number, since it is larger than the sum of its proper divisors (1).

121398857 is an equidigital number, since it uses as much as digits as its factorization.

121398857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 44.

The square root of 121398857 is about 11018.1149476669. The cubic root of 121398857 is about 495.1516142720.

The spelling of 121398857 in words is "one hundred twenty-one million, three hundred ninety-eight thousand, eight hundred fifty-seven".