281100020 has 54 divisors (see below), whose sum is σ = 620900658. Its totient is φ = 106891488.

The previous prime is 281100007. The next prime is 281100023. The reversal of 281100020 is 20001182.

It can be written as a sum of positive squares in only one way, i.e., 224880016 + 56220004 = 14996^2 + 7498^2 .

It is a junction number, because it is equal to n+sod(n) for n = 281099968 and 281100004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (281100023) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1724459 + ... + 1724621.

Almost surely, 2^281100020 is an apocalyptic number.

281100020 is a gapful number since it is divisible by the number (20) 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 281100020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310450329).

281100020 is an abundant number, since it is smaller than the sum of its proper divisors (339800638).

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

281100020 is a wasteful number, since it uses less digits than its factorization.

281100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381 (or 193 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 281100020 is about 16766.0376952934. The cubic root of 281100020 is about 655.0688659795.

The spelling of 281100020 in words is "two hundred eighty-one million, one hundred thousand, twenty".