15845522641 has 27 divisors (see below), whose sum is σ = 17979317937. Its totient is φ = 13957463520.

The previous prime is 15845522597. The next prime is 15845522717. The reversal of 15845522641 is 14622554851.

The square root of 15845522641 is 125879.

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

It can be written as a sum of positive squares in 4 ways, for example, as 12675382225 + 3170140416 = 112585^2 + 56304^2 .

It is not a de Polignac number, because 15845522641 - 2⁷ = 15845522513 is a prime.

It is a super-2 number, since 2×15845522641² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15845522041) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 37637611 + ... + 37638031.

Almost surely, 2^15845522641 is an apocalyptic number.

15845522641 is the 125879-th square number.

15845522641 is the 62940-th centered octagonal number.

It is an amenable number.

15845522641 is a deficient number, since it is larger than the sum of its proper divisors (2133795296).

15845522641 is an frugal number, since it uses more digits than its factorization.

15845522641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 914 (or 457 counting only the distinct ones).

The product of its digits is 384000, while the sum is 43.

The spelling of 15845522641 in words is "fifteen billion, eight hundred forty-five million, five hundred twenty-two thousand, six hundred forty-one".