475681951809 has 45 divisors (see below), whose sum is σ = 716052708217. Its totient is φ = 314700464736.

The previous prime is 475681951769. The next prime is 475681951861. The reversal of 475681951809 is 908159186574.

The square root of 475681951809 is 689697.

It is a perfect power (a square), and thus also a powerful number.

475681951809 is a `hidden beast` number, since 4 + 7 + 568 + 19 + 51 + 8 + 0 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 60523380225 + 415158571584 = 246015^2 + 644328^2 .

It is not a de Polignac number, because 475681951809 - 2³¹ = 473534468161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (475681951889) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 1222832587 + ... + 1222832975.

Almost surely, 2^475681951809 is an apocalyptic number.

475681951809 is the 689697-th square number.

475681951809 is the 344849-th centered octagonal number.

It is an amenable number.

475681951809 is a deficient number, since it is larger than the sum of its proper divisors (240370756408).

475681951809 is an frugal number, since it uses more digits than its factorization.

475681951809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1184 (or 589 counting only the distinct ones).

The product of its (nonzero) digits is 21772800, while the sum is 63.

The spelling of 475681951809 in words is "four hundred seventy-five billion, six hundred eighty-one million, nine hundred fifty-one thousand, eight hundred nine".