13661147817801 has 81 divisors (see below), whose sum is σ = 22418181700551. Its totient is φ = 8010185752800.

The previous prime is 13661147817781. The next prime is 13661147817809. The reversal of 13661147817801 is 10871874116631.

The square root of 13661147817801 is 3696099.

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

13661147817801 is a `hidden beast` number, since 1 + 3 + 6 + 611 + 4 + 7 + 8 + 17 + 8 + 0 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 7561172025 + 13653586645776 = 86955^2 + 3695076^2 .

It is not a de Polignac number, because 13661147817801 - 2¹⁹ = 13661147293513 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (13661147817809) 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, 3781107471 + ... + 3781111083.

Almost surely, 2^{13661147817801} is an apocalyptic number.

13661147817801 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

13661147817801 is the 3696099-th square number.

13661147817801 is the 1848050-th centered octagonal number.

It is an amenable number.

13661147817801 is a deficient number, since it is larger than the sum of its proper divisors (8757033882750).

13661147817801 is an frugal number, since it uses more digits than its factorization.

13661147817801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7316 (or 3658 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 54.

The spelling of 13661147817801 in words is "thirteen trillion, six hundred sixty-one billion, one hundred forty-seven million, eight hundred seventeen thousand, eight hundred one".