196785990409849 has 81 divisors (see below), whose sum is σ = 217008414893799. Its totient is φ = 178409773117440.

The previous prime is 196785990409823. The next prime is 196785990409901. The reversal of 196785990409849 is 948904099587691.

The square root of 196785990409849 is 14028043.

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

It can be written as a sum of positive squares in 13 ways, for example, as 173704307574249 + 23081682835600 = 13179693^2 + 4804340^2 .

It is not a de Polignac number, because 196785990409849 - 2⁵ = 196785990409817 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 196785990409849.

It is not an unprimeable number, because it can be changed into a prime (196785990400849) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 1087215416539 + ... + 1087215416719.

Almost surely, 2^{196785990409849} is an apocalyptic number.

196785990409849 is the 14028043-rd square number.

196785990409849 is the 7014022-nd centered octagonal number.

It is an amenable number.

196785990409849 is a deficient number, since it is larger than the sum of its proper divisors (20222424483950).

196785990409849 is an frugal number, since it uses more digits than its factorization.

196785990409849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 684 (or 342 counting only the distinct ones).

The product of its (nonzero) digits is 12697896960, while the sum is 88.

The spelling of 196785990409849 in words is "one hundred ninety-six trillion, seven hundred eighty-five billion, nine hundred ninety million, four hundred nine thousand, eight hundred forty-nine".