15405961 has 4 divisors (see below), whose sum is σ = 16312212. Its totient is φ = 14499712.

The previous prime is 15405959. The next prime is 15406009. The reversal of 15405961 is 16950451.

15405961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 6405961 + 9000000 = 2531^2 + 3000^2 .

It is a cyclic number.

It is not a de Polignac number, because 15405961 - 2¹ = 15405959 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15405661) 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, 453100 + ... + 453133.

It is an arithmetic number, because the mean of its divisors is an integer number (4078053).

Almost surely, 2^15405961 is an apocalyptic number.

It is an amenable number.

15405961 is a deficient number, since it is larger than the sum of its proper divisors (906251).

15405961 is an equidigital number, since it uses as much as digits as its factorization.

15405961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 906250.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 15405961 is about 3925.0428023144. The cubic root of 15405961 is about 248.8262902451.

The spelling of 15405961 in words is "fifteen million, four hundred five thousand, nine hundred sixty-one".