420681 has 4 divisors (see below), whose sum is σ = 560912. Its totient is φ = 280452.

The previous prime is 420677. The next prime is 420683. The reversal of 420681 is 186024.

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 not a de Polignac number, because 420681 - 2² = 420677 is a prime.

It is a super-2 number, since 2×420681² = 353945007522, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 420681.

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 3 ways as a sum of consecutive naturals, for example, 70111 + ... + 70116.

It is an arithmetic number, because the mean of its divisors is an integer number (140228).

2⁴²⁰⁶⁸¹ is an apocalyptic number.

It is an amenable number.

420681 is a deficient number, since it is larger than the sum of its proper divisors (140231).

420681 is a wasteful number, since it uses less digits than its factorization.

420681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140230.

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 420681 is about 648.5992599441. The cubic root of 420681 is about 74.9291775880.

The spelling of 420681 in words is "four hundred twenty thousand, six hundred eighty-one".