191045045569 has 27 divisors (see below), whose sum is σ = 236142057897. Its totient is φ = 154078412544.

The previous prime is 191045045563. The next prime is 191045045599. The reversal of 191045045569 is 965540540191.

The square root of 191045045569 is 437087.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 10147943169 + 180897102400 = 100737^2 + 425320^2 .

It is not a de Polignac number, because 191045045569 - 2⁹ = 191045045057 is a prime.

It is a super-2 number, since 2×191045045569² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191045045563) 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 in 26 ways as a sum of consecutive naturals, for example, 52011517 + ... + 52015189.

Almost surely, 2^191045045569 is an apocalyptic number.

191045045569 is the 437087-th square number.

191045045569 is the 218544-th centered octagonal number.

It is an amenable number.

191045045569 is a deficient number, since it is larger than the sum of its proper divisors (45097012328).

191045045569 is an frugal number, since it uses more digits than its factorization.

191045045569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7394 (or 3697 counting only the distinct ones).

The product of its (nonzero) digits is 972000, while the sum is 49.

Multiplying 191045045569 by its sum of digits (49), we get a square (9361207232881 = 3059609²).

191045045569 divided by its sum of digits (49) gives a square (3898878481 = 62441²).

The spelling of 191045045569 in words is "one hundred ninety-one billion, forty-five million, forty-five thousand, five hundred sixty-nine".