281005240645 has 8 divisors (see below), whose sum is σ = 337230932760. Its totient is φ = 224787763200.

The previous prime is 281005240631. The next prime is 281005240717. The reversal of 281005240645 is 546042500182.

It can be written as a sum of positive squares in 4 ways, for example, as 3806149636 + 277199091009 = 61694^2 + 526497^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 281005240645 - 2²¹ = 281003143493 is a prime.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1978156 + ... + 2115445.

It is an arithmetic number, because the mean of its divisors is an integer number (42153866595).

Almost surely, 2^281005240645 is an apocalyptic number.

It is an amenable number.

281005240645 is a deficient number, since it is larger than the sum of its proper divisors (56225692115).

281005240645 is a wasteful number, since it uses less digits than its factorization.

281005240645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4107335.

The product of its (nonzero) digits is 76800, while the sum is 37.

The spelling of 281005240645 in words is "two hundred eighty-one billion, five million, two hundred forty thousand, six hundred forty-five".