1649891664989 has 8 divisors (see below), whose sum is σ = 1654084480128. Its totient is φ = 1645703069040.

The previous prime is 1649891664979. The next prime is 1649891665021. The reversal of 1649891664989 is 9894661989461.

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 1649891664989 - 2¹⁶ = 1649891599453 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 (1649891664979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 270977 + ... + 1836630.

It is an arithmetic number, because the mean of its divisors is an integer number (206760560016).

Almost surely, 2^{1649891664989} is an apocalyptic number.

It is an amenable number.

1649891664989 is a deficient number, since it is larger than the sum of its proper divisors (4192815139).

1649891664989 is a wasteful number, since it uses less digits than its factorization.

1649891664989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2109595.

The product of its digits is 1451188224, while the sum is 80.

The spelling of 1649891664989 in words is "one trillion, six hundred forty-nine billion, eight hundred ninety-one million, six hundred sixty-four thousand, nine hundred eighty-nine".