15645898678897 has 4 divisors (see below), whose sum is σ = 15902388821236. Its totient is φ = 15389408536560.

The previous prime is 15645898678843. The next prime is 15645898678901. The reversal of 15645898678897 is 79887689854651.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8524905025536 + 7120993653361 = 2919744^2 + 2668519^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15645898678897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15645898678997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128245071078 + ... + 128245071199.

It is an arithmetic number, because the mean of its divisors is an integer number (3975597205309).

Almost surely, 2^{15645898678897} is an apocalyptic number.

It is an amenable number.

15645898678897 is a deficient number, since it is larger than the sum of its proper divisors (256490142339).

15645898678897 is an equidigital number, since it uses as much as digits as its factorization.

15645898678897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256490142338.

The product of its digits is 58525286400, while the sum is 91.

The spelling of 15645898678897 in words is "fifteen trillion, six hundred forty-five billion, eight hundred ninety-eight million, six hundred seventy-eight thousand, eight hundred ninety-seven".