421817656 has 32 divisors (see below), whose sum is σ = 862545600. Its totient is φ = 192216960.

The previous prime is 421817653. The next prime is 421817663. The reversal of 421817656 is 656718124.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421817653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17455 + ... + 33886.

It is an arithmetic number, because the mean of its divisors is an integer number (26954550).

Almost surely, 2^421817656 is an apocalyptic number.

It is an amenable number.

421817656 is an abundant number, since it is smaller than the sum of its proper divisors (440727944).

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

421817656 is a wasteful number, since it uses less digits than its factorization.

421817656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51439 (or 51435 counting only the distinct ones).

The product of its digits is 80640, while the sum is 40.

The square root of 421817656 is about 20538.1999211226. The cubic root of 421817656 is about 749.9660168306.

The spelling of 421817656 in words is "four hundred twenty-one million, eight hundred seventeen thousand, six hundred fifty-six".