420687 has 8 divisors (see below), whose sum is σ = 623280. Its totient is φ = 280440.

The previous prime is 420683. The next prime is 420691. The reversal of 420687 is 786024.

It is an interprime number because it is at equal distance from previous prime (420683) and next prime (420691).

It is not a de Polignac number, because 420687 - 2² = 420683 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 15581 = 420687 / (4 + 2 + 0 + 6 + 8 + 7).

It is a self number, because there is not a number n which added to its sum of digits gives 420687.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 420687.

It is not an unprimeable number, because it can be changed into a prime (420683) 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, 7764 + ... + 7817.

It is an arithmetic number, because the mean of its divisors is an integer number (77910).

2⁴²⁰⁶⁸⁷ is an apocalyptic number.

420687 is a deficient number, since it is larger than the sum of its proper divisors (202593).

420687 is a wasteful number, since it uses less digits than its factorization.

420687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15590 (or 15584 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 420687 is about 648.6038852798. The cubic root of 420687 is about 74.9295338143.

The spelling of 420687 in words is "four hundred twenty thousand, six hundred eighty-seven".