19497245881521 has 4 divisors (see below), whose sum is σ = 25996327842032. Its totient is φ = 12998163921012.

The previous prime is 19497245881483. The next prime is 19497245881601. The reversal of 19497245881521 is 12518854279491.

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.

It is not a de Polignac number, because 19497245881521 - 2²³ = 19497237492913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19497245881021) 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, 3249540980251 + ... + 3249540980256.

It is an arithmetic number, because the mean of its divisors is an integer number (6499081960508).

Almost surely, 2^{19497245881521} is an apocalyptic number.

It is an amenable number.

19497245881521 is a deficient number, since it is larger than the sum of its proper divisors (6499081960511).

19497245881521 is an equidigital number, since it uses as much as digits as its factorization.

19497245881521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6499081960510.

The product of its digits is 58060800, while the sum is 66.

The spelling of 19497245881521 in words is "nineteen trillion, four hundred ninety-seven billion, two hundred forty-five million, eight hundred eighty-one thousand, five hundred twenty-one".