121001999857 has 2 divisors, whose sum is σ = 121001999858. Its totient is φ = 121001999856.

The previous prime is 121001999773. The next prime is 121001999863. The reversal of 121001999857 is 758999100121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 117350094096 + 3651905761 = 342564^2 + 60431^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121001999857 is a prime.

It is not a weakly prime, because it can be changed into another prime (121005999857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60500999928 + 60500999929.

It is an arithmetic number, because the mean of its divisors is an integer number (60500999929).

Almost surely, 2^121001999857 is an apocalyptic number.

It is an amenable number.

121001999857 is a deficient number, since it is larger than the sum of its proper divisors (1).

121001999857 is an equidigital number, since it uses as much as digits as its factorization.

121001999857 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 408240, while the sum is 52.

The spelling of 121001999857 in words is "one hundred twenty-one billion, one million, nine hundred ninety-nine thousand, eight hundred fifty-seven".