19651943453 has 2 divisors, whose sum is σ = 19651943454. Its totient is φ = 19651943452.

The previous prime is 19651943419. The next prime is 19651943473. The reversal of 19651943453 is 35434915691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12055600804 + 7596342649 = 109798^2 + 87157^2 .

It is a cyclic number.

It is not a de Polignac number, because 19651943453 - 2²⁰ = 19650894877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19651943473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9825971726 + 9825971727.

It is an arithmetic number, because the mean of its divisors is an integer number (9825971727).

Almost surely, 2^19651943453 is an apocalyptic number.

It is an amenable number.

19651943453 is a deficient number, since it is larger than the sum of its proper divisors (1).

19651943453 is an equidigital number, since it uses as much as digits as its factorization.

19651943453 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1749600, while the sum is 50.

The spelling of 19651943453 in words is "nineteen billion, six hundred fifty-one million, nine hundred forty-three thousand, four hundred fifty-three".