6472381661 has 8 divisors (see below), whose sum is σ = 6859265400. Its totient is φ = 6086181888.

The previous prime is 6472381651. The next prime is 6472381667. The reversal of 6472381661 is 1661832746.

It can be written as a sum of positive squares in 4 ways, for example, as 1042902436 + 5429479225 = 32294^2 + 73685^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 6472381661 - 2¹⁰ = 6472380637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6472381667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151436 + ... + 189413.

It is an arithmetic number, because the mean of its divisors is an integer number (857408175).

Almost surely, 2^6472381661 is an apocalyptic number.

It is an amenable number.

6472381661 is a deficient number, since it is larger than the sum of its proper divisors (386883739).

6472381661 is a wasteful number, since it uses less digits than its factorization.

6472381661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341983.

The product of its digits is 290304, while the sum is 44.

The square root of 6472381661 is about 80451.1134851470. The cubic root of 6472381661 is about 1863.6086013055.

The spelling of 6472381661 in words is "six billion, four hundred seventy-two million, three hundred eighty-one thousand, six hundred sixty-one".