390649 has 4 divisors (see below), whose sum is σ = 446464. Its totient is φ = 334836.

The previous prime is 390647. The next prime is 390653. The reversal of 390649 is 946093.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 390649 - 2¹ = 390647 is a prime.

It is an Ulam number.

It is a Duffinian number.

390649 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 390649.

It is not an unprimeable number, because it can be changed into a prime (390647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27897 + ... + 27910.

It is an arithmetic number, because the mean of its divisors is an integer number (111616).

2³⁹⁰⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

390649 is a deficient number, since it is larger than the sum of its proper divisors (55815).

390649 is an equidigital number, since it uses as much as digits as its factorization.

390649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55814.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 390649 is about 625.0191997051. The cubic root of 390649 is about 73.1019405217.

The spelling of 390649 in words is "three hundred ninety thousand, six hundred forty-nine".