281001906 has 32 divisors (see below), whose sum is σ = 657316800. Its totient is φ = 88737120.

The previous prime is 281001901. The next prime is 281001907. The reversal of 281001906 is 609100182.

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

It is a self number, because there is not a number n which added to its sum of digits gives 281001906.

It is not an unprimeable number, because it can be changed into a prime (281001901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135915 + ... + 137966.

It is an arithmetic number, because the mean of its divisors is an integer number (20541150).

Almost surely, 2^281001906 is an apocalyptic number.

281001906 is an abundant number, since it is smaller than the sum of its proper divisors (376314894).

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

281001906 is a wasteful number, since it uses less digits than its factorization.

281001906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273911 (or 273905 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 281001906 is about 16763.1114653575. Note that the first 3 decimals coincide. The cubic root of 281001906 is about 654.9926429257.

The spelling of 281001906 in words is "two hundred eighty-one million, one thousand, nine hundred six".