851649 has 8 divisors (see below), whose sum is σ = 1202400. Its totient is φ = 534336.

The previous prime is 851647. The next prime is 851659. The reversal of 851649 is 946158.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 851649 - 2¹ = 851647 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (851647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8299 + ... + 8400.

It is an arithmetic number, because the mean of its divisors is an integer number (150300).

2⁸⁵¹⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

851649 is a deficient number, since it is larger than the sum of its proper divisors (350751).

851649 is a wasteful number, since it uses less digits than its factorization.

851649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16719.

The product of its digits is 8640, while the sum is 33.

The square root of 851649 is about 922.8483082284. The cubic root of 851649 is about 94.7880408279.

The spelling of 851649 in words is "eight hundred fifty-one thousand, six hundred forty-nine".