199640368242225 has 45 divisors (see below), whose sum is σ = 369804151238907. Its totient is φ = 106474523956560.

The previous prime is 199640368242187. The next prime is 199640368242233. The reversal of 199640368242225 is 522242863046991.

The square root of 199640368242225 is 14129415.

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

199640368242225 is a `hidden beast` number, since 1 + 9 + 9 + 6 + 4 + 0 + 368 + 2 + 42 + 225 = 666.

It can be written as a sum of positive squares in only one way, i.e., 71870532567201 + 127769835675024 = 8477649^2 + 11303532^2 .

It is a tau number, because it is divible by the number of its divisors (45).

It is not a de Polignac number, because 199640368242225 - 2⁷ = 199640368242097 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 635666682 + ... + 635980668.

Almost surely, 2^{199640368242225} is an apocalyptic number.

199640368242225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

199640368242225 is the 14129415-th square number.

199640368242225 is the 7064708-th centered octagonal number.

It is an amenable number.

199640368242225 is a deficient number, since it is larger than the sum of its proper divisors (170163782996682).

199640368242225 is an frugal number, since it uses more digits than its factorization.

199640368242225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 627996 (or 313995 counting only the distinct ones).

The product of its (nonzero) digits is 89579520, while the sum is 63.

The spelling of 199640368242225 in words is "one hundred ninety-nine trillion, six hundred forty billion, three hundred sixty-eight million, two hundred forty-two thousand, two hundred twenty-five".