801551 has 2 divisors, whose sum is σ = 801552. Its totient is φ = 801550.

The previous prime is 801539. The next prime is 801557. The reversal of 801551 is 155108.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 801551 - 2⁶ = 801487 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (801557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 400775 + 400776.

It is an arithmetic number, because the mean of its divisors is an integer number (400776).

2⁸⁰¹⁵⁵¹ is an apocalyptic number.

801551 is a deficient number, since it is larger than the sum of its proper divisors (1).

801551 is an equidigital number, since it uses as much as digits as its factorization.

801551 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 200, while the sum is 20.

The square root of 801551 is about 895.2938065239. The cubic root of 801551 is about 92.8917304795.

Adding to 801551 its reverse (155108), we get a palindrome (956659).

The spelling of 801551 in words is "eight hundred one thousand, five hundred fifty-one".