1649564681736 has 64 divisors (see below), whose sum is σ = 4213616889600. Its totient is φ = 537905105408.

The previous prime is 1649564681711. The next prime is 1649564681747. The reversal of 1649564681736 is 6371864659461.

It is a Smith number, since the sum of its digits (66) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2088970 + ... + 2768198.

It is an arithmetic number, because the mean of its divisors is an integer number (65837763900).

Almost surely, 2^{1649564681736} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1649564681736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2106808444800).

1649564681736 is an abundant number, since it is smaller than the sum of its proper divisors (2564052207864).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1649564681736 is a wasteful number, since it uses less digits than its factorization.

1649564681736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681438 (or 681434 counting only the distinct ones).

The product of its digits is 156764160, while the sum is 66.

The spelling of 1649564681736 in words is "one trillion, six hundred forty-nine billion, five hundred sixty-four million, six hundred eighty-one thousand, seven hundred thirty-six".