25435521202409 has 2 divisors, whose sum is σ = 25435521202410. Its totient is φ = 25435521202408.

The previous prime is 25435521202391. The next prime is 25435521202457. The reversal of 25435521202409 is 90420212553452.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21012689281600 + 4422831920809 = 4583960^2 + 2103053^2 .

It is a cyclic number.

It is not a de Polignac number, because 25435521202409 - 2²⁰ = 25435520153833 is a prime.

It is a super-2 number, since 2×25435521202409² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 25435521202409.

It is not a weakly prime, because it can be changed into another prime (25435521202459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12717760601204 + 12717760601205.

It is an arithmetic number, because the mean of its divisors is an integer number (12717760601205).

Almost surely, 2^{25435521202409} is an apocalyptic number.

It is an amenable number.

25435521202409 is a deficient number, since it is larger than the sum of its proper divisors (1).

25435521202409 is an equidigital number, since it uses as much as digits as its factorization.

25435521202409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864000, while the sum is 44.

The spelling of 25435521202409 in words is "twenty-five trillion, four hundred thirty-five billion, five hundred twenty-one million, two hundred two thousand, four hundred nine".