15461561 has 4 divisors (see below), whose sum is σ = 15486324. Its totient is φ = 15436800.

The previous prime is 15461557. The next prime is 15461587. The reversal of 15461561 is 16516451.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9610000 + 5851561 = 3100^2 + 2419^2 .

It is a cyclic number.

It is not a de Polignac number, because 15461561 - 2² = 15461557 is a prime.

It is a Duffinian number.

It is a zygodrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (15461521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11420 + ... + 12701.

It is an arithmetic number, because the mean of its divisors is an integer number (3871581).

Almost surely, 2^15461561 is an apocalyptic number.

It is an amenable number.

15461561 is a deficient number, since it is larger than the sum of its proper divisors (24763).

15461561 is an equidigital number, since it uses as much as digits as its factorization.

15461561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24762.

The product of its digits is 3600, while the sum is 29.

The square root of 15461561 is about 3932.1191487543. The cubic root of 15461561 is about 249.1252682806.

The spelling of 15461561 in words is "fifteen million, four hundred sixty-one thousand, five hundred sixty-one".