13705561 has 2 divisors, whose sum is σ = 13705562. Its totient is φ = 13705560.

The previous prime is 13705513. The next prime is 13705589. The reversal of 13705561 is 16550731.

It is an a-pointer prime, because the next prime (13705589) can be obtained adding 13705561 to its sum of digits (28).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13097161 + 608400 = 3619^2 + 780^2 .

It is a cyclic number.

It is not a de Polignac number, because 13705561 - 2¹⁵ = 13672793 is a prime.

It is a super-4 number, since 4×13705561⁴ (a number of 30 digits) contains 4444 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13705511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6852780 + 6852781.

It is an arithmetic number, because the mean of its divisors is an integer number (6852781).

Almost surely, 2^13705561 is an apocalyptic number.

It is an amenable number.

13705561 is a deficient number, since it is larger than the sum of its proper divisors (1).

13705561 is an equidigital number, since it uses as much as digits as its factorization.

13705561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3150, while the sum is 28.

The square root of 13705561 is about 3702.1022406195. The cubic root of 13705561 is about 239.3126222994.

The spelling of 13705561 in words is "thirteen million, seven hundred five thousand, five hundred sixty-one".