651281 has 2 divisors, whose sum is σ = 651282. Its totient is φ = 651280.

The previous prime is 651271. The next prime is 651289. The reversal of 651281 is 182156.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 625681 + 25600 = 791^2 + 160^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-651281 is a prime.

It is a super-2 number, since 2×651281² = 848333881922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is an Ulam number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 651281.

It is not a weakly prime, because it can be changed into another prime (651289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 325640 + 325641.

It is an arithmetic number, because the mean of its divisors is an integer number (325641).

2⁶⁵¹²⁸¹ is an apocalyptic number.

It is an amenable number.

651281 is a deficient number, since it is larger than the sum of its proper divisors (1).

651281 is an equidigital number, since it uses as much as digits as its factorization.

651281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 480, while the sum is 23.

The square root of 651281 is about 807.0198262744. The cubic root of 651281 is about 86.6807784384.

The spelling of 651281 in words is "six hundred fifty-one thousand, two hundred eighty-one".