1020120251 has 2 divisors, whose sum is σ = 1020120252. Its totient is φ = 1020120250.

The previous prime is 1020120247. The next prime is 1020120253. The reversal of 1020120251 is 1520210201.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1020120251 - 2² = 1020120247 is a prime.

Together with 1020120253, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1020120253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510060125 + 510060126.

It is an arithmetic number, because the mean of its divisors is an integer number (510060126).

Almost surely, 2^1020120251 is an apocalyptic number.

1020120251 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020120251 is an equidigital number, since it uses as much as digits as its factorization.

1020120251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 1020120251 is about 31939.3213922901. The cubic root of 1020120251 is about 1006.6622659754.

Adding to 1020120251 its reverse (1520210201), we get a palindrome (2540330452).

The spelling of 1020120251 in words is "one billion, twenty million, one hundred twenty thousand, two hundred fifty-one".