25716321 has 6 divisors (see below), whose sum is σ = 37145810. Its totient is φ = 17144208.

The previous prime is 25716293. The next prime is 25716337. The reversal of 25716321 is 12361752.

It is a happy number.

25716321 is a `hidden beast` number, since 25 + 7 + 1 + 632 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 25401600 + 314721 = 5040^2 + 561^2 .

It is not a de Polignac number, because 25716321 - 2¹⁹ = 25192033 is a prime.

It is a super-2 number, since 2×25716321² = 1322658331550082, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25716371) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1428676 + ... + 1428693.

Almost surely, 2^25716321 is an apocalyptic number.

It is an amenable number.

25716321 is a deficient number, since it is larger than the sum of its proper divisors (11429489).

25716321 is a wasteful number, since it uses less digits than its factorization.

25716321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2857375 (or 2857372 counting only the distinct ones).

The product of its digits is 2520, while the sum is 27.

The square root of 25716321 is about 5071.1262062780. The cubic root of 25716321 is about 295.1682311528.

The spelling of 25716321 in words is "twenty-five million, seven hundred sixteen thousand, three hundred twenty-one".