25221505105 has 16 divisors (see below), whose sum is σ = 30404684304. Its totient is φ = 20084762880.

The previous prime is 25221505093. The next prime is 25221505121. The reversal of 25221505105 is 50150512252.

It can be written as a sum of positive squares in 8 ways, for example, as 151216209 + 25070288896 = 12297^2 + 158336^2 .

It is not a de Polignac number, because 25221505105 - 2⁷ = 25221504977 is a prime.

It is a super-2 number, since 2×25221505105² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1505475 + ... + 1522135.

It is an arithmetic number, because the mean of its divisors is an integer number (1900292769).

Almost surely, 2^25221505105 is an apocalyptic number.

It is an amenable number.

25221505105 is a deficient number, since it is larger than the sum of its proper divisors (5183179199).

25221505105 is a wasteful number, since it uses less digits than its factorization.

25221505105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18036.

The product of its (nonzero) digits is 5000, while the sum is 28.

The spelling of 25221505105 in words is "twenty-five billion, two hundred twenty-one million, five hundred five thousand, one hundred five".