646490 has 16 divisors (see below), whose sum is σ = 1253448. Its totient is φ = 238656.

The previous prime is 646453. The next prime is 646519. The reversal of 646490 is 94646.

646490 is nontrivially palindromic in base 8.

It can be written as a sum of positive squares in 4 ways, for example, as 450241 + 196249 = 671^2 + 443^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2357 + ... + 2616.

2⁶⁴⁶⁴⁹⁰ is an apocalyptic number.

646490 is a deficient number, since it is larger than the sum of its proper divisors (606958).

646490 is a wasteful number, since it uses less digits than its factorization.

646490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4993.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 646490 is about 804.0460185835. The cubic root of 646490 is about 86.4677059886.

The spelling of 646490 in words is "six hundred forty-six thousand, four hundred ninety".