15640441 has 2 divisors, whose sum is σ = 15640442. Its totient is φ = 15640440.

The previous prime is 15640409. The next prime is 15640451. The reversal of 15640441 is 14404651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14600041 + 1040400 = 3821^2 + 1020^2 .

It is an emirp because it is prime and its reverse (14404651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15640441 - 2⁵ = 15640409 is a prime.

It is not a weakly prime, because it can be changed into another prime (15640451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7820220 + 7820221.

It is an arithmetic number, because the mean of its divisors is an integer number (7820221).

Almost surely, 2^15640441 is an apocalyptic number.

It is an amenable number.

15640441 is a deficient number, since it is larger than the sum of its proper divisors (1).

15640441 is an equidigital number, since it uses as much as digits as its factorization.

15640441 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 15640441 is about 3954.7997420856. The cubic root of 15640441 is about 250.0823248875.

The spelling of 15640441 in words is "fifteen million, six hundred forty thousand, four hundred forty-one".