102400121 has 2 divisors, whose sum is σ = 102400122. Its totient is φ = 102400120.

The previous prime is 102400069. The next prime is 102400153. The reversal of 102400121 is 121004201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60668521 + 41731600 = 7789^2 + 6460^2 .

It is an emirp because it is prime and its reverse (121004201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 102400121 - 2¹⁰ = 102399097 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (102400021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51200060 + 51200061.

It is an arithmetic number, because the mean of its divisors is an integer number (51200061).

Almost surely, 2^102400121 is an apocalyptic number.

It is an amenable number.

102400121 is a deficient number, since it is larger than the sum of its proper divisors (1).

102400121 is an equidigital number, since it uses as much as digits as its factorization.

102400121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 102400121 is about 10119.2944912182. The cubic root of 102400121 is about 467.8430223880.

Adding to 102400121 its reverse (121004201), we get a palindrome (223404322).

It can be divided in two parts, 102400 and 121, that multiplied together give a square (12390400 = 3520²).

The spelling of 102400121 in words is "one hundred two million, four hundred thousand, one hundred twenty-one".