11901858308649 has 135 divisors (see below), whose sum is σ = 18545262986613. Its totient is φ = 7606796541696.

The previous prime is 11901858308647. The next prime is 11901858308677. The reversal of 11901858308649 is 94680385810911.

The square root of 11901858308649 is 3449907.

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

11901858308649 is a `hidden beast` number, since 1 + 1 + 9 + 0 + 1 + 8 + 583 + 0 + 8 + 6 + 49 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 810081002025 + 11091777306624 = 900045^2 + 3330432^2 .

It is not a de Polignac number, because 11901858308649 - 2¹ = 11901858308647 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11901858308647) 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 134 ways as a sum of consecutive naturals, for example, 133728744997 + ... + 133728745085.

Almost surely, 2^{11901858308649} is an apocalyptic number.

11901858308649 is the 3449907-th square number.

11901858308649 is the 1724954-th centered octagonal number.

It is an amenable number.

11901858308649 is a deficient number, since it is larger than the sum of its proper divisors (6643404677964).

11901858308649 is an frugal number, since it uses more digits than its factorization.

11901858308649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 454 (or 224 counting only the distinct ones).

The product of its (nonzero) digits is 14929920, while the sum is 63.

The spelling of 11901858308649 in words is "eleven trillion, nine hundred one billion, eight hundred fifty-eight million, three hundred eight thousand, six hundred forty-nine".