1687248641 has 8 divisors (see below), whose sum is σ = 1818592104. Its totient is φ = 1556127360.

The previous prime is 1687248637. The next prime is 1687248671. The reversal of 1687248641 is 1468427861.

It can be written as a sum of positive squares in 4 ways, for example, as 142444225 + 1544804416 = 11935^2 + 39304^2 .

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 1687248641 - 2² = 1687248637 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1687248671) 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, 39596 + ... + 70301.

It is an arithmetic number, because the mean of its divisors is an integer number (227324013).

Almost surely, 2^1687248641 is an apocalyptic number.

It is an amenable number.

1687248641 is a deficient number, since it is larger than the sum of its proper divisors (131343463).

1687248641 is a wasteful number, since it uses less digits than its factorization.

1687248641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111091.

The product of its digits is 516096, while the sum is 47.

The square root of 1687248641 is about 41076.1322546318. The cubic root of 1687248641 is about 1190.4916738126.

The spelling of 1687248641 in words is "one billion, six hundred eighty-seven million, two hundred forty-eight thousand, six hundred forty-one".