820464 has 20 divisors (see below), whose sum is σ = 2119656. Its totient is φ = 273472.

The previous prime is 820459. The next prime is 820481. The reversal of 820464 is 464028.

It is a super-2 number, since 2×820464² = 1346322350592, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

820464 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8499 + ... + 8594.

2⁸²⁰⁴⁶⁴ is an apocalyptic number.

It is an amenable number.

820464 is an abundant number, since it is smaller than the sum of its proper divisors (1299192).

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

820464 is a wasteful number, since it uses less digits than its factorization.

820464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17104 (or 17098 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 820464 is about 905.7946787214. The cubic root of 820464 is about 93.6166673511.

The spelling of 820464 in words is "eight hundred twenty thousand, four hundred sixty-four".