1420440257 has 2 divisors, whose sum is σ = 1420440258. Its totient is φ = 1420440256.

The previous prime is 1420440221. The next prime is 1420440277. The reversal of 1420440257 is 7520440241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1379082496 + 41357761 = 37136^2 + 6431^2 .

It is an emirp because it is prime and its reverse (7520440241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1420440257 - 2¹⁶ = 1420374721 is a prime.

It is not a weakly prime, because it can be changed into another prime (1420440277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 710220128 + 710220129.

It is an arithmetic number, because the mean of its divisors is an integer number (710220129).

Almost surely, 2^1420440257 is an apocalyptic number.

It is an amenable number.

1420440257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1420440257 is an equidigital number, since it uses as much as digits as its factorization.

1420440257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8960, while the sum is 29.

The square root of 1420440257 is about 37688.7285139735. The cubic root of 1420440257 is about 1124.1070133735.

Adding to 1420440257 its reverse (7520440241), we get a palindrome (8940880498).

The spelling of 1420440257 in words is "one billion, four hundred twenty million, four hundred forty thousand, two hundred fifty-seven".