1002020251 has 2 divisors, whose sum is σ = 1002020252. Its totient is φ = 1002020250.

The previous prime is 1002020249. The next prime is 1002020291. The reversal of 1002020251 is 1520202001.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1002020251 - 2¹ = 1002020249 is a prime.

Together with 1002020249, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1002020291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 501010125 + 501010126.

It is an arithmetic number, because the mean of its divisors is an integer number (501010126).

Almost surely, 2^1002020251 is an apocalyptic number.

1002020251 is a deficient number, since it is larger than the sum of its proper divisors (1).

1002020251 is an equidigital number, since it uses as much as digits as its factorization.

1002020251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 1002020251 is about 31654.7034577802. The cubic root of 1002020251 is about 1000.6729640178.

Adding to 1002020251 its reverse (1520202001), we get a palindrome (2522222252).

The spelling of 1002020251 in words is "one billion, two million, twenty thousand, two hundred fifty-one".