121889730857 has 2 divisors, whose sum is σ = 121889730858. Its totient is φ = 121889730856.

The previous prime is 121889730827. The next prime is 121889730869. The reversal of 121889730857 is 758037988121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 119612914201 + 2276816656 = 345851^2 + 47716^2 .

It is an emirp because it is prime and its reverse (758037988121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121889730857 - 2¹⁸ = 121889468713 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121889730796 and 121889730805.

It is not a weakly prime, because it can be changed into another prime (121889730817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60944865428 + 60944865429.

It is an arithmetic number, because the mean of its divisors is an integer number (60944865429).

Almost surely, 2^121889730857 is an apocalyptic number.

It is an amenable number.

121889730857 is a deficient number, since it is larger than the sum of its proper divisors (1).

121889730857 is an equidigital number, since it uses as much as digits as its factorization.

121889730857 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6773760, while the sum is 59.

The spelling of 121889730857 in words is "one hundred twenty-one billion, eight hundred eighty-nine million, seven hundred thirty thousand, eight hundred fifty-seven".