420440664 has 128 divisors (see below), whose sum is σ = 1277337600. Its totient is φ = 112648320.

The previous prime is 420440663. The next prime is 420440681. The reversal of 420440664 is 466044024.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420440663) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 340929 + ... + 342159.

It is an arithmetic number, because the mean of its divisors is an integer number (9979200).

Almost surely, 2^420440664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 420440664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (638668800).

420440664 is an abundant number, since it is smaller than the sum of its proper divisors (856896936).

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

420440664 is a wasteful number, since it uses less digits than its factorization.

420440664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1373 (or 1369 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 30.

The square root of 420440664 is about 20504.6498141275. The cubic root of 420440664 is about 749.1490580065.

Adding to 420440664 its reverse (466044024), we get a palindrome (886484688).

The spelling of 420440664 in words is "four hundred twenty million, four hundred forty thousand, six hundred sixty-four".