197781503893 has 2 divisors, whose sum is σ = 197781503894. Its totient is φ = 197781503892.

The previous prime is 197781503891. The next prime is 197781503923. The reversal of 197781503893 is 398305187791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 197426482929 + 355020964 = 444327^2 + 18842^2 .

It is a cyclic number.

It is not a de Polignac number, because 197781503893 - 2¹ = 197781503891 is a prime.

Together with 197781503891, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197781503891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98890751946 + 98890751947.

It is an arithmetic number, because the mean of its divisors is an integer number (98890751947).

Almost surely, 2^197781503893 is an apocalyptic number.

It is an amenable number.

197781503893 is a deficient number, since it is larger than the sum of its proper divisors (1).

197781503893 is an equidigital number, since it uses as much as digits as its factorization.

197781503893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11430720, while the sum is 61.

The spelling of 197781503893 in words is "one hundred ninety-seven billion, seven hundred eighty-one million, five hundred three thousand, eight hundred ninety-three".