15660000649 has 4 divisors (see below), whose sum is σ = 15728987664. Its totient is φ = 15591013636.

The previous prime is 15660000647. The next prime is 15660000749. The reversal of 15660000649 is 94600006651.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 94600006651 = 6397 ⋅14788183.

It is a cyclic number.

It is not a de Polignac number, because 15660000649 - 2¹ = 15660000647 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15660000647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34493167 + ... + 34493620.

It is an arithmetic number, because the mean of its divisors is an integer number (3932246916).

Almost surely, 2^15660000649 is an apocalyptic number.

It is an amenable number.

15660000649 is a deficient number, since it is larger than the sum of its proper divisors (68987015).

15660000649 is an equidigital number, since it uses as much as digits as its factorization.

15660000649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68987014.

The product of its (nonzero) digits is 38880, while the sum is 37.

The spelling of 15660000649 in words is "fifteen billion, six hundred sixty million, six hundred forty-nine", and thus it is an aban number.