25644563 has 16 divisors (see below), whose sum is σ = 31242240. Its totient is φ = 20571936.

The previous prime is 25644529. The next prime is 25644581. The reversal of 25644563 is 36544652.

25644563 = T₄₈₂ + T₄₈₃ + ... + T₆₄₂.

It is a happy number.

It is not a de Polignac number, because 25644563 - 2⁶ = 25644499 is a prime.

It is a super-2 number, since 2×25644563² = 1315287222921938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25644523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5873 + ... + 9261.

It is an arithmetic number, because the mean of its divisors is an integer number (1952640).

Almost surely, 2^25644563 is an apocalyptic number.

25644563 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

25644563 is a deficient number, since it is larger than the sum of its proper divisors (5597677).

25644563 is a wasteful number, since it uses less digits than its factorization.

25644563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3466.

The product of its digits is 86400, while the sum is 35.

The square root of 25644563 is about 5064.0461095847. The cubic root of 25644563 is about 294.8934327325.

The spelling of 25644563 in words is "twenty-five million, six hundred forty-four thousand, five hundred sixty-three".