11401561 has 2 divisors, whose sum is σ = 11401562. Its totient is φ = 11401560.

The previous prime is 11401549. The next prime is 11401601. The reversal of 11401561 is 16510411.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7054336 + 4347225 = 2656^2 + 2085^2 .

It is a cyclic number.

It is not a de Polignac number, because 11401561 - 2¹⁵ = 11368793 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (11402561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5700780 + 5700781.

It is an arithmetic number, because the mean of its divisors is an integer number (5700781).

Almost surely, 2^11401561 is an apocalyptic number.

It is an amenable number.

11401561 is a deficient number, since it is larger than the sum of its proper divisors (1).

11401561 is an equidigital number, since it uses as much as digits as its factorization.

11401561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 19.

The square root of 11401561 is about 3376.6197594636. The cubic root of 11401561 is about 225.0719835524.

Adding to 11401561 its reverse (16510411), we get a palindrome (27911972).

It can be divided in two parts, 1140 and 1561, that added together give a triangular number (2701 = T₇₃).

The spelling of 11401561 in words is "eleven million, four hundred one thousand, five hundred sixty-one".