25016721 has 8 divisors (see below), whose sum is σ = 34431744. Its totient is φ = 16139760.

The previous prime is 25016681. The next prime is 25016729. The reversal of 25016721 is 12761052.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-25016721 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 25016691 and 25016700.

It is not an unprimeable number, because it can be changed into a prime (25016729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 134406 + ... + 134591.

It is an arithmetic number, because the mean of its divisors is an integer number (4303968).

Almost surely, 2^25016721 is an apocalyptic number.

It is an amenable number.

25016721 is a deficient number, since it is larger than the sum of its proper divisors (9415023).

25016721 is a wasteful number, since it uses less digits than its factorization.

25016721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269031.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 25016721 is about 5001.6718205016. The cubic root of 25016721 is about 292.4669492936.

Adding to 25016721 its reverse (12761052), we get a palindrome (37777773).

The spelling of 25016721 in words is "twenty-five million, sixteen thousand, seven hundred twenty-one".