25750721 has 4 divisors (see below), whose sum is σ = 26000832. Its totient is φ = 25500612.

The previous prime is 25750717. The next prime is 25750729. The reversal of 25750721 is 12705752.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25750721 - 2² = 25750717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25750729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124901 + ... + 125106.

It is an arithmetic number, because the mean of its divisors is an integer number (6500208).

Almost surely, 2^25750721 is an apocalyptic number.

It is an amenable number.

25750721 is a deficient number, since it is larger than the sum of its proper divisors (250111).

25750721 is a wasteful number, since it uses less digits than its factorization.

25750721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250110.

The product of its (nonzero) digits is 4900, while the sum is 29.

The square root of 25750721 is about 5074.5168242898. The cubic root of 25750721 is about 295.2997852611.

The spelling of 25750721 in words is "twenty-five million, seven hundred fifty thousand, seven hundred twenty-one".