995551 has 2 divisors, whose sum is σ = 995552. Its totient is φ = 995550.

The previous prime is 995549. The next prime is 995567. The reversal of 995551 is 155599.

It is a weak prime.

It is an emirp because it is prime and its reverse (155599) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 995551 - 2¹ = 995549 is a prime.

It is a super-2 number, since 2×995551² = 1982243587202, which contains 22 as substring.

Together with 995549, it forms a pair of twin primes.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (995531) 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, 497775 + 497776.

It is an arithmetic number, because the mean of its divisors is an integer number (497776).

2⁹⁹⁵⁵⁵¹ is an apocalyptic number.

995551 is a deficient number, since it is larger than the sum of its proper divisors (1).

995551 is an equidigital number, since it uses as much as digits as its factorization.

995551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10125, while the sum is 34.

The square root of 995551 is about 997.7730202807. The cubic root of 995551 is about 99.8514795259.

It can be divided in two parts, 9955 and 51, that multiplied together give a palindrome (507705).

The spelling of 995551 in words is "nine hundred ninety-five thousand, five hundred fifty-one".