19685715645849 has 32 divisors (see below), whose sum is σ = 28760042572800. Its totient is φ = 11878126925760.

The previous prime is 19685715645847. The next prime is 19685715645857. The reversal of 19685715645849 is 94854651758691.

It is not a de Polignac number, because 19685715645849 - 2¹ = 19685715645847 is a prime.

It is a super-2 number, since 2×19685715645849² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19685715645847) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 249213042 + ... + 249292020.

It is an arithmetic number, because the mean of its divisors is an integer number (898751330400).

Almost surely, 2^{19685715645849} is an apocalyptic number.

It is an amenable number.

19685715645849 is a deficient number, since it is larger than the sum of its proper divisors (9074326926951).

19685715645849 is a wasteful number, since it uses less digits than its factorization.

19685715645849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112205.

The product of its digits is 2612736000, while the sum is 78.

The spelling of 19685715645849 in words is "nineteen trillion, six hundred eighty-five billion, seven hundred fifteen million, six hundred forty-five thousand, eight hundred forty-nine".