55102121 has 2 divisors, whose sum is σ = 55102122. Its totient is φ = 55102120.

The previous prime is 55102067. The next prime is 55102129. The reversal of 55102121 is 12120155.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45091225 + 10010896 = 6715^2 + 3164^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55102121 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 55102121.

It is not a weakly prime, because it can be changed into another prime (55102129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27551060 + 27551061.

It is an arithmetic number, because the mean of its divisors is an integer number (27551061).

Almost surely, 2^55102121 is an apocalyptic number.

It is an amenable number.

55102121 is a deficient number, since it is larger than the sum of its proper divisors (1).

55102121 is an equidigital number, since it uses as much as digits as its factorization.

55102121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 100, while the sum is 17.

The square root of 55102121 is about 7423.0802905532. The cubic root of 55102121 is about 380.5304710417.

Adding to 55102121 its reverse (12120155), we get a palindrome (67222276).

The spelling of 55102121 in words is "fifty-five million, one hundred two thousand, one hundred twenty-one".