475661781 has 32 divisors (see below), whose sum is σ = 840376320. Its totient is φ = 259986672.

The previous prime is 475661779. The next prime is 475661783. The reversal of 475661781 is 187166574.

475661781 is a `hidden beast` number, since 4 + 7 + 566 + 1 + 7 + 81 = 666.

It is an interprime number because it is at equal distance from previous prime (475661779) and next prime (475661783).

It is not a de Polignac number, because 475661781 - 2¹ = 475661779 is a prime.

It is a super-2 number, since 2×475661781² = 452508259808183922, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (475661783) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50365 + ... + 59058.

It is an arithmetic number, because the mean of its divisors is an integer number (26261760).

Almost surely, 2^475661781 is an apocalyptic number.

It is an amenable number.

475661781 is a deficient number, since it is larger than the sum of its proper divisors (364714539).

475661781 is a wasteful number, since it uses less digits than its factorization.

475661781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109462 (or 109456 counting only the distinct ones).

The product of its digits is 282240, while the sum is 45.

The square root of 475661781 is about 21809.6717306795. The cubic root of 475661781 is about 780.6075591803.

The spelling of 475661781 in words is "four hundred seventy-five million, six hundred sixty-one thousand, seven hundred eighty-one".