100400256 has 256 divisors, whose sum is σ = 342720000. Its totient is φ = 28615680.

The previous prime is 100400207. The next prime is 100400257. The reversal of 100400256 is 652004001.

It is a happy number.

100400256 is a `hidden beast` number, since 10 + 0 + 400 + 256 = 666.

It is a super-2 number, since 2×100400256² = 20160422809731072, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (100400257) 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, 722235 + ... + 722373.

It is an arithmetic number, because the mean of its divisors is an integer number (1338750).

Almost surely, 2^100400256 is an apocalyptic number.

100400256 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 100400256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171360000).

100400256 is an abundant number, since it is smaller than the sum of its proper divisors (242319744).

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

100400256 is a wasteful number, since it uses less digits than its factorization.

100400256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 100400256 is about 10019.9928143687. The cubic root of 100400256 is about 464.7773335591. Note that the first 3 decimals are identical.

Adding to 100400256 its reverse (652004001), we get a palindrome (752404257).

The spelling of 100400256 in words is "one hundred million, four hundred thousand, two hundred fifty-six".