987631 has 2 divisors, whose sum is σ = 987632. Its totient is φ = 987630.

The previous prime is 987607. The next prime is 987659. The reversal of 987631 is 136789.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 987631 - 2⁵ = 987599 is a prime.

It is a super-2 number, since 2×987631² = 1950829984322, which contains 22 as substring.

It is an Ulam number.

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 (985631) 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, 493815 + 493816.

It is an arithmetic number, because the mean of its divisors is an integer number (493816).

2⁹⁸⁷⁶³¹ is an apocalyptic number.

987631 is a deficient number, since it is larger than the sum of its proper divisors (1).

987631 is an equidigital number, since it uses as much as digits as its factorization.

987631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 34.

The square root of 987631 is about 993.7962567851. The cubic root of 987631 is about 99.5859883087.

The spelling of 987631 in words is "nine hundred eighty-seven thousand, six hundred thirty-one".