25511551 has 8 divisors (see below), whose sum is σ = 27557600. Its totient is φ = 23477472.

The previous prime is 25511539. The next prime is 25511567. The reversal of 25511551 is 15511552.

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

It is a cyclic number.

It is not a de Polignac number, because 25511551 - 2¹⁷ = 25380479 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 (25511581) 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, 1726 + ... + 7348.

It is an arithmetic number, because the mean of its divisors is an integer number (3444700).

Almost surely, 2^25511551 is an apocalyptic number.

25511551 is a deficient number, since it is larger than the sum of its proper divisors (2046049).

25511551 is a wasteful number, since it uses less digits than its factorization.

25511551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5985.

The product of its digits is 1250, while the sum is 25.

The square root of 25511551 is about 5050.8960591166. The cubic root of 25511551 is about 294.3827022896.

Subtracting from 25511551 its reverse (15511552), we obtain a palindrome (9999999).

It can be divided in two parts, 25511 and 551, that added together give a palindrome (26062).

The spelling of 25511551 in words is "twenty-five million, five hundred eleven thousand, five hundred fifty-one".