19997558690769 has 27 divisors (see below), whose sum is σ = 31750260908457. Its totient is φ = 12119643102600.

The previous prime is 19997558690749. The next prime is 19997558690777. The reversal of 19997558690769 is 96709685579991.

The square root of 19997558690769 is 4471863.

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

19997558690769 is a `hidden beast` number, since 19 + 9 + 9 + 7 + 5 + 586 + 9 + 0 + 7 + 6 + 9 = 666.

It is not a de Polignac number, because 19997558690769 - 2²⁹ = 19997021819857 is a prime.

It is a super-2 number, since 2×19997558690769² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19997558690749) 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 26 ways as a sum of consecutive naturals, for example, 147503724 + ... + 147639234.

Almost surely, 2^{19997558690769} is an apocalyptic number.

19997558690769 is the 4471863-rd square number.

19997558690769 is the 2235932-nd centered octagonal number.

It is an amenable number.

19997558690769 is a deficient number, since it is larger than the sum of its proper divisors (11752702217688).

19997558690769 is an frugal number, since it uses more digits than its factorization.

19997558690769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271050 (or 135525 counting only the distinct ones).

The product of its (nonzero) digits is 20832487200, while the sum is 90.

The spelling of 19997558690769 in words is "nineteen trillion, nine hundred ninety-seven billion, five hundred fifty-eight million, six hundred ninety thousand, seven hundred sixty-nine".