25005551 has 4 divisors (see below), whose sum is σ = 25537632. Its totient is φ = 24473472.

The previous prime is 25005527. The next prime is 25005553. The reversal of 25005551 is 15550052.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25005551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25005553) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 265970 + ... + 266063.

It is an arithmetic number, because the mean of its divisors is an integer number (6384408).

Almost surely, 2^25005551 is an apocalyptic number.

25005551 is a deficient number, since it is larger than the sum of its proper divisors (532081).

25005551 is an equidigital number, since it uses as much as digits as its factorization.

25005551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532080.

The product of its (nonzero) digits is 1250, while the sum is 23.

The square root of 25005551 is about 5000.5550691898. Note that the first 3 decimals coincide. The cubic root of 25005551 is about 292.4234138497.

The spelling of 25005551 in words is "twenty-five million, five thousand, five hundred fifty-one".