100421856 has 240 divisors, whose sum is σ = 326020464. Its totient is φ = 30191616.

The previous prime is 100421851. The next prime is 100421861. The reversal of 100421856 is 658124001.

It is an interprime number because it is at equal distance from previous prime (100421851) and next prime (100421861).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100421851) 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 39 ways as a sum of consecutive naturals, for example, 1894726 + ... + 1894778.

Almost surely, 2^100421856 is an apocalyptic number.

100421856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 100421856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163010232).

100421856 is an abundant number, since it is smaller than the sum of its proper divisors (225598608).

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

100421856 is a wasteful number, since it uses less digits than its factorization.

100421856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 100421856 is about 10021.0706014876. The cubic root of 100421856 is about 464.8106617296.

Adding to 100421856 its reverse (658124001), we get a palindrome (758545857).

The spelling of 100421856 in words is "one hundred million, four hundred twenty-one thousand, eight hundred fifty-six".