25984795421 has 4 divisors (see below), whose sum is σ = 27983625852. Its totient is φ = 23985964992.

The previous prime is 25984795411. The next prime is 25984795429. The reversal of 25984795421 is 12459748952.

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 8715156025 + 17269639396 = 93355^2 + 131414^2 .

It is a cyclic number.

It is not a de Polignac number, because 25984795421 - 2¹⁸ = 25984533277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25984795429) 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, 999415196 + ... + 999415221.

It is an arithmetic number, because the mean of its divisors is an integer number (6995906463).

Almost surely, 2^25984795421 is an apocalyptic number.

It is an amenable number.

25984795421 is a deficient number, since it is larger than the sum of its proper divisors (1998830431).

25984795421 is a wasteful number, since it uses less digits than its factorization.

25984795421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1998830430.

The product of its digits is 7257600, while the sum is 56.

The spelling of 25984795421 in words is "twenty-five billion, nine hundred eighty-four million, seven hundred ninety-five thousand, four hundred twenty-one".