1639065541 has 2 divisors, whose sum is σ = 1639065542. Its totient is φ = 1639065540.

The previous prime is 1639065539. The next prime is 1639065611. The reversal of 1639065541 is 1455609361.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1406625025 + 232440516 = 37505^2 + 15246^2 .

It is a cyclic number.

It is not a de Polignac number, because 1639065541 - 2¹ = 1639065539 is a prime.

Together with 1639065539, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1639065494 and 1639065503.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1639065041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 819532770 + 819532771.

It is an arithmetic number, because the mean of its divisors is an integer number (819532771).

Almost surely, 2^1639065541 is an apocalyptic number.

It is an amenable number.

1639065541 is a deficient number, since it is larger than the sum of its proper divisors (1).

1639065541 is an equidigital number, since it uses as much as digits as its factorization.

1639065541 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 97200, while the sum is 40.

The square root of 1639065541 is about 40485.3744085441. The cubic root of 1639065541 is about 1179.0496851696.

The spelling of 1639065541 in words is "one billion, six hundred thirty-nine million, sixty-five thousand, five hundred forty-one".