102420251 has 2 divisors, whose sum is σ = 102420252. Its totient is φ = 102420250.

The previous prime is 102420239. The next prime is 102420277. The reversal of 102420251 is 152024201.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 102420251 - 2¹⁰ = 102419227 is a prime.

It is not a weakly prime, because it can be changed into another prime (102420211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51210125 + 51210126.

It is an arithmetic number, because the mean of its divisors is an integer number (51210126).

Almost surely, 2^102420251 is an apocalyptic number.

102420251 is a deficient number, since it is larger than the sum of its proper divisors (1).

102420251 is an equidigital number, since it uses as much as digits as its factorization.

102420251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 102420251 is about 10120.2890768989. The cubic root of 102420251 is about 467.8736768537.

Adding to 102420251 its reverse (152024201), we get a palindrome (254444452).

The spelling of 102420251 in words is "one hundred two million, four hundred twenty thousand, two hundred fifty-one".