25449016321 has 4 divisors (see below), whose sum is σ = 25711377412. Its totient is φ = 25186655232.

The previous prime is 25449016319. The next prime is 25449016339. The reversal of 25449016321 is 12361094452.

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 15734942721 + 9714073600 = 125439^2 + 98560^2 .

It is a cyclic number.

It is not a de Polignac number, because 25449016321 - 2¹ = 25449016319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25449016921) 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, 131180400 + ... + 131180593.

It is an arithmetic number, because the mean of its divisors is an integer number (6427844353).

Almost surely, 2^25449016321 is an apocalyptic number.

It is an amenable number.

25449016321 is a deficient number, since it is larger than the sum of its proper divisors (262361091).

25449016321 is an equidigital number, since it uses as much as digits as its factorization.

25449016321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262361090.

The product of its (nonzero) digits is 51840, while the sum is 37.

The spelling of 25449016321 in words is "twenty-five billion, four hundred forty-nine million, sixteen thousand, three hundred twenty-one".