15605551065 has 16 divisors (see below), whose sum is σ = 26889565248. Its totient is φ = 7682732736.

The previous prime is 15605551057. The next prime is 15605551109. The reversal of 15605551065 is 56015550651.

It is not a de Polignac number, because 15605551065 - 2³ = 15605551057 is a prime.

It is a super-4 number, since 4×15605551065⁴ (a number of 42 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 40014039 + ... + 40014428.

It is an arithmetic number, because the mean of its divisors is an integer number (1680597828).

Almost surely, 2^15605551065 is an apocalyptic number.

15605551065 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

15605551065 is a deficient number, since it is larger than the sum of its proper divisors (11284014183).

15605551065 is a wasteful number, since it uses less digits than its factorization.

15605551065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80028488.

The product of its (nonzero) digits is 112500, while the sum is 39.

The spelling of 15605551065 in words is "fifteen billion, six hundred five million, five hundred fifty-one thousand, sixty-five".