25479619309 has 4 divisors (see below), whose sum is σ = 25480211004. Its totient is φ = 25479027616.

The previous prime is 25479619279. The next prime is 25479619331. The reversal of 25479619309 is 90391697452.

It is a happy number.

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 10190296809 + 15289322500 = 100947^2 + 123650^2 .

It is a cyclic number.

It is not a de Polignac number, because 25479619309 - 2²¹ = 25477522157 is a prime.

It is a super-2 number, since 2×25479619309² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25479619309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25479611309) 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, 225712 + ... + 319225.

It is an arithmetic number, because the mean of its divisors is an integer number (6370052751).

Almost surely, 2^25479619309 is an apocalyptic number.

It is an amenable number.

25479619309 is a deficient number, since it is larger than the sum of its proper divisors (591695).

25479619309 is an equidigital number, since it uses as much as digits as its factorization.

25479619309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 591694.

The product of its (nonzero) digits is 3674160, while the sum is 55.

The spelling of 25479619309 in words is "twenty-five billion, four hundred seventy-nine million, six hundred nineteen thousand, three hundred nine".