20151222025 has 81 divisors (see below), whose sum is σ = 28768566463. Its totient is φ = 13991084800.

The previous prime is 20151222023. The next prime is 20151222037. The reversal of 20151222025 is 52022215102.

The square root of 20151222025 is 141955.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 17959484169 + 2191737856 = 134013^2 + 46816^2 .

It is not a de Polignac number, because 20151222025 - 2¹ = 20151222023 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20151221987 and 20151222005.

It is not an unprimeable number, because it can be changed into a prime (20151222023) by changing a digit.

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 80 ways as a sum of consecutive naturals, for example, 226418181 + ... + 226418269.

Almost surely, 2^20151222025 is an apocalyptic number.

20151222025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20151222025 is the 141955-th square number.

20151222025 is the 70978-th centered octagonal number.

It is an amenable number.

20151222025 is a deficient number, since it is larger than the sum of its proper divisors (8617344438).

20151222025 is an equidigital number, since it uses as much as digits as its factorization.

20151222025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268 (or 134 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

Adding to 20151222025 its reverse (52022215102), we get a palindrome (72173437127).

The spelling of 20151222025 in words is "twenty billion, one hundred fifty-one million, two hundred twenty-two thousand, twenty-five".