1645481738 has 16 divisors (see below), whose sum is σ = 2622417120. Its totient is φ = 772152336.

The previous prime is 1645481711. The next prime is 1645481777. The reversal of 1645481738 is 8371845461.

It is a super-2 number, since 2×1645481738² = 5415220300183001288, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1645481692 and 1645481701.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 198281 + ... + 206412.

It is an arithmetic number, because the mean of its divisors is an integer number (163901070).

Almost surely, 2^1645481738 is an apocalyptic number.

1645481738 is a deficient number, since it is larger than the sum of its proper divisors (976935382).

1645481738 is a wasteful number, since it uses less digits than its factorization.

1645481738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404821.

The product of its digits is 645120, while the sum is 47.

The square root of 1645481738 is about 40564.5379364785. The cubic root of 1645481738 is about 1180.5861633388.

The spelling of 1645481738 in words is "one billion, six hundred forty-five million, four hundred eighty-one thousand, seven hundred thirty-eight".