1643141636 has 12 divisors (see below), whose sum is σ = 2875803420. Its totient is φ = 821483520.

The previous prime is 1643141623. The next prime is 1643141651. The reversal of 1643141636 is 6361413461.

It can be written as a sum of positive squares in 2 ways, for example, as 824838400 + 818303236 = 28720^2 + 28606^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1643141596 and 1643141605.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39956 + ... + 69876.

It is an arithmetic number, because the mean of its divisors is an integer number (239650285).

Almost surely, 2^1643141636 is an apocalyptic number.

It is an amenable number.

1643141636 is a deficient number, since it is larger than the sum of its proper divisors (1232661784).

1643141636 is a wasteful number, since it uses less digits than its factorization.

1643141636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43654 (or 43652 counting only the distinct ones).

The product of its digits is 31104, while the sum is 35.

The square root of 1643141636 is about 40535.6834899820. The cubic root of 1643141636 is about 1180.0262457056.

The spelling of 1643141636 in words is "one billion, six hundred forty-three million, one hundred forty-one thousand, six hundred thirty-six".