25820581989 has 8 divisors (see below), whose sum is σ = 34428184960. Its totient is φ = 17213350176.

The previous prime is 25820581973. The next prime is 25820581991. The reversal of 25820581989 is 98918502852.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 25820581989 - 2⁴ = 25820581973 is a prime.

It is a super-2 number, since 2×25820581989² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25820581489) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 226164 + ... + 320610.

It is an arithmetic number, because the mean of its divisors is an integer number (4303523120).

Almost surely, 2^25820581989 is an apocalyptic number.

It is an amenable number.

25820581989 is a deficient number, since it is larger than the sum of its proper divisors (8607602971).

25820581989 is an equidigital number, since it uses as much as digits as its factorization.

25820581989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185579.

The product of its (nonzero) digits is 4147200, while the sum is 57.

The spelling of 25820581989 in words is "twenty-five billion, eight hundred twenty million, five hundred eighty-one thousand, nine hundred eighty-nine".