15989855401 has 27 divisors (see below), whose sum is σ = 17690882853. Its totient is φ = 14445762240.

The previous prime is 15989855377. The next prime is 15989855419. The reversal of 15989855401 is 10455898951.

It is a happy number.

The square root of 15989855401 is 126451.

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

15989855401 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1421365401 + 14568490000 = 37701^2 + 120700^2 .

It is not a de Polignac number, because 15989855401 - 2⁹ = 15989854889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15989855491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 116714205 + ... + 116714341.

Almost surely, 2^15989855401 is an apocalyptic number.

15989855401 is the 126451-st square number.

15989855401 is the 63226-th centered octagonal number.

It is an amenable number.

15989855401 is a deficient number, since it is larger than the sum of its proper divisors (1701027452).

15989855401 is an frugal number, since it uses more digits than its factorization.

15989855401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 442 (or 221 counting only the distinct ones).

The product of its (nonzero) digits is 2592000, while the sum is 55.

The spelling of 15989855401 in words is "fifteen billion, nine hundred eighty-nine million, eight hundred fifty-five thousand, four hundred one".