1641555437824 has 27 divisors (see below), whose sum is σ = 3276739469577. Its totient is φ = 820767469056.

The previous prime is 1641555437801. The next prime is 1641555437827. The reversal of 1641555437824 is 4287345551461.

The square root of 1641555437824 is 1281232.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 748847929600 + 892707508224 = 865360^2 + 944832^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1641555437827) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 20459674 + ... + 20539750.

Almost surely, 2^{1641555437824} is an apocalyptic number.

1641555437824 is the 1281232-nd square number.

It is an amenable number.

1641555437824 is a deficient number, since it is larger than the sum of its proper divisors (1635184031753).

1641555437824 is an frugal number, since it uses more digits than its factorization.

1641555437824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160170 (or 80079 counting only the distinct ones).

The product of its digits is 16128000, while the sum is 55.

The spelling of 1641555437824 in words is "one trillion, six hundred forty-one billion, five hundred fifty-five million, four hundred thirty-seven thousand, eight hundred twenty-four".