25387642225 has 27 divisors (see below), whose sum is σ = 34614675361. Its totient is φ = 18457366400.

The previous prime is 25387642219. The next prime is 25387642249. The reversal of 25387642225 is 52224678352.

The square root of 25387642225 is 159335.

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

It can be written as a sum of positive squares in 4 ways, for example, as 7718852449 + 17668789776 = 87857^2 + 132924^2 .

It is not a de Polignac number, because 25387642225 - 2⁷ = 25387642097 is a prime.

It is a super-4 number, since 4×25387642225⁴ (a number of 43 digits) contains 4444 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 (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 8761977 + ... + 8764873.

Almost surely, 2^25387642225 is an apocalyptic number.

25387642225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

25387642225 is the 159335-th square number.

25387642225 is the 79668-th centered octagonal number.

It is an amenable number.

25387642225 is a deficient number, since it is larger than the sum of its proper divisors (9227033136).

25387642225 is an frugal number, since it uses more digits than its factorization.

25387642225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5826 (or 2913 counting only the distinct ones).

The product of its digits is 1612800, while the sum is 46.

The spelling of 25387642225 in words is "twenty-five billion, three hundred eighty-seven million, six hundred forty-two thousand, two hundred twenty-five".