820487 has 4 divisors (see below), whose sum is σ = 824160. Its totient is φ = 816816.

The previous prime is 820481. The next prime is 820489. The reversal of 820487 is 784028.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 820487 - 2⁸ = 820231 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820481) 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, 1478 + ... + 1955.

It is an arithmetic number, because the mean of its divisors is an integer number (206040).

2⁸²⁰⁴⁸⁷ is an apocalyptic number.

820487 is a deficient number, since it is larger than the sum of its proper divisors (3673).

820487 is a wasteful number, since it uses less digits than its factorization.

820487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3672.

The product of its (nonzero) digits is 3584, while the sum is 29.

The square root of 820487 is about 905.8073746664. The cubic root of 820487 is about 93.6175421257.

The spelling of 820487 in words is "eight hundred twenty thousand, four hundred eighty-seven".