1641287787 has 8 divisors (see below), whose sum is σ = 2193842640. Its totient is φ = 1091462400.

The previous prime is 1641287779. The next prime is 1641287789. The reversal of 1641287787 is 7877821461.

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

It is not a de Polignac number, because 1641287787 - 2³ = 1641287779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1641287789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 680962 + ... + 683367.

It is an arithmetic number, because the mean of its divisors is an integer number (274230330).

Almost surely, 2^1641287787 is an apocalyptic number.

1641287787 is a deficient number, since it is larger than the sum of its proper divisors (552554853).

1641287787 is a wasteful number, since it uses less digits than its factorization.

1641287787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1364733.

The product of its digits is 1053696, while the sum is 51.

The square root of 1641287787 is about 40512.8101592570. The cubic root of 1641287787 is about 1179.5822966167.

The spelling of 1641287787 in words is "one billion, six hundred forty-one million, two hundred eighty-seven thousand, seven hundred eighty-seven".