996637489 has 2 divisors, whose sum is σ = 996637490. Its totient is φ = 996637488.

The previous prime is 996637487. The next prime is 996637501. The reversal of 996637489 is 984736699.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 546858225 + 449779264 = 23385^2 + 21208^2 .

It is an emirp because it is prime and its reverse (984736699) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 996637489 - 2¹ = 996637487 is a prime.

Together with 996637487, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (996637487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498318744 + 498318745.

It is an arithmetic number, because the mean of its divisors is an integer number (498318745).

Almost surely, 2^996637489 is an apocalyptic number.

It is an amenable number.

996637489 is a deficient number, since it is larger than the sum of its proper divisors (1).

996637489 is an equidigital number, since it uses as much as digits as its factorization.

996637489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17635968, while the sum is 61.

The square root of 996637489 is about 31569.5658665114. The cubic root of 996637489 is about 998.8779043723.

Subtracting from 996637489 its product of digits (17635968), we obtain a square (979001521 = 31289²).

The spelling of 996637489 in words is "nine hundred ninety-six million, six hundred thirty-seven thousand, four hundred eighty-nine".