649998 has 16 divisors (see below), whose sum is σ = 1444560. Its totient is φ = 216648.

The previous prime is 649991. The next prime is 650011. The reversal of 649998 is 899946.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 649998.

It is not an unprimeable number, because it can be changed into a prime (649991) by changing a digit.

649998 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 in 7 ways as a sum of consecutive naturals, for example, 5965 + ... + 6072.

It is an arithmetic number, because the mean of its divisors is an integer number (90285).

2⁶⁴⁹⁹⁹⁸ is an apocalyptic number.

649998 is an abundant number, since it is smaller than the sum of its proper divisors (794562).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

649998 is a wasteful number, since it uses less digits than its factorization.

649998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12048 (or 12042 counting only the distinct ones).

The product of its digits is 139968, while the sum is 45.

The square root of 649998 is about 806.2245344816. The cubic root of 649998 is about 86.6238216890.

The spelling of 649998 in words is "six hundred forty-nine thousand, nine hundred ninety-eight".