477139661 has 4 divisors (see below), whose sum is σ = 477757692. Its totient is φ = 476521632.

The previous prime is 477139657. The next prime is 477139681. The reversal of 477139661 is 166931774.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 166931774 = 2 ⋅83465887.

It can be written as a sum of positive squares in 2 ways, for example, as 268337161 + 208802500 = 16381^2 + 14450^2 .

It is a cyclic number.

It is not a de Polignac number, because 477139661 - 2² = 477139657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (477139681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 307856 + ... + 309401.

It is an arithmetic number, because the mean of its divisors is an integer number (119439423).

Almost surely, 2^477139661 is an apocalyptic number.

It is an amenable number.

477139661 is a deficient number, since it is larger than the sum of its proper divisors (618031).

477139661 is an equidigital number, since it uses as much as digits as its factorization.

477139661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 618030.

The product of its digits is 190512, while the sum is 44.

The square root of 477139661 is about 21843.5267527934. The cubic root of 477139661 is about 781.4151719377.

The spelling of 477139661 in words is "four hundred seventy-seven million, one hundred thirty-nine thousand, six hundred sixty-one".