281625755820021 has 12 divisors (see below), whose sum is σ = 406796485000620. Its totient is φ = 187748783913600.

The previous prime is 281625755819999. The next prime is 281625755820107. The reversal of 281625755820021 is 120028557526182.

281625755820021 is a `hidden beast` number, since 2 + 8 + 1 + 6 + 2 + 57 + 5 + 582 + 0 + 0 + 2 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 101169117257796 + 180456638562225 = 10058286^2 + 13433415^2 .

It is not a de Polignac number, because 281625755820021 - 2¹⁸ = 281625755557877 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 281625755820021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (281625755827021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 142293126 + ... + 144258743.

It is an arithmetic number, because the mean of its divisors is an integer number (33899707083385).

Almost surely, 2^{281625755820021} is an apocalyptic number.

It is an amenable number.

281625755820021 is a deficient number, since it is larger than the sum of its proper divisors (125170729180599).

281625755820021 is a wasteful number, since it uses less digits than its factorization.

281625755820021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286661076 (or 286661073 counting only the distinct ones).

The product of its (nonzero) digits is 5376000, while the sum is 54.

The spelling of 281625755820021 in words is "two hundred eighty-one trillion, six hundred twenty-five billion, seven hundred fifty-five million, eight hundred twenty thousand, twenty-one".