15540021105 has 64 divisors (see below), whose sum is σ = 29151553536. Its totient is φ = 6920640000.

The previous prime is 15540021103. The next prime is 15540021197. The reversal of 15540021105 is 50112004551.

It is not a de Polignac number, because 15540021105 - 2¹ = 15540021103 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (15540021103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3489130 + ... + 3493580.

It is an arithmetic number, because the mean of its divisors is an integer number (455493024).

Almost surely, 2^15540021105 is an apocalyptic number.

15540021105 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

15540021105 is a deficient number, since it is larger than the sum of its proper divisors (13611532431).

15540021105 is a wasteful number, since it uses less digits than its factorization.

15540021105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5318.

The product of its (nonzero) digits is 1000, while the sum is 24.

Adding to 15540021105 its reverse (50112004551), we get a palindrome (65652025656).

The spelling of 15540021105 in words is "fifteen billion, five hundred forty million, twenty-one thousand, one hundred five".