19729496977 has 4 divisors (see below), whose sum is σ = 19730039920. Its totient is φ = 19728954036.

The previous prime is 19729496947. The next prime is 19729496981. The reversal of 19729496977 is 77969492791.

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: 77969492791 = 67 ⋅1163723773.

It is a cyclic number.

It is not a de Polignac number, because 19729496977 - 2¹¹ = 19729494929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19729496947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 212727 + ... + 291052.

It is an arithmetic number, because the mean of its divisors is an integer number (4932509980).

Almost surely, 2^19729496977 is an apocalyptic number.

It is an amenable number.

19729496977 is a deficient number, since it is larger than the sum of its proper divisors (542943).

19729496977 is an equidigital number, since it uses as much as digits as its factorization.

19729496977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 542942.

The product of its digits is 108020304, while the sum is 70.

It can be divided in two parts, 1972 and 9496977, that added together give a palindrome (9498949).

The spelling of 19729496977 in words is "nineteen billion, seven hundred twenty-nine million, four hundred ninety-six thousand, nine hundred seventy-seven".