421777 has 4 divisors (see below), whose sum is σ = 424116. Its totient is φ = 419440.

The previous prime is 421741. The next prime is 421783. The reversal of 421777 is 777124.

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

It can be written as a sum of positive squares in 2 ways, for example, as 408321 + 13456 = 639^2 + 116^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (421717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 874 + ... + 1267.

It is an arithmetic number, because the mean of its divisors is an integer number (106029).

2⁴²¹⁷⁷⁷ is an apocalyptic number.

It is an amenable number.

421777 is a deficient number, since it is larger than the sum of its proper divisors (2339).

421777 is a wasteful number, since it uses less digits than its factorization.

421777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2338.

The product of its digits is 2744, while the sum is 28.

The square root of 421777 is about 649.4436080215. The cubic root of 421777 is about 74.9941921429.

The spelling of 421777 in words is "four hundred twenty-one thousand, seven hundred seventy-seven", and thus it is an iban number.