15506666065 has 48 divisors (see below), whose sum is σ = 20925647568. Its totient is φ = 11019008000.

The previous prime is 15506666057. The next prime is 15506666069. The reversal of 15506666065 is 56066660551.

It can be written as a sum of positive squares in 8 ways, for example, as 1006412176 + 14500253889 = 31724^2 + 120417^2 .

It is not a de Polignac number, because 15506666065 - 2³ = 15506666057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15506666069) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9009405 + ... + 9011125.

It is an arithmetic number, because the mean of its divisors is an integer number (435950991).

Almost surely, 2^15506666065 is an apocalyptic number.

It is an amenable number.

15506666065 is a deficient number, since it is larger than the sum of its proper divisors (5418981503).

15506666065 is a wasteful number, since it uses less digits than its factorization.

15506666065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2082 (or 2071 counting only the distinct ones).

The product of its (nonzero) digits is 972000, while the sum is 46.

The spelling of 15506666065 in words is "fifteen billion, five hundred six million, six hundred sixty-six thousand, sixty-five".