25121551 has 16 divisors (see below), whose sum is σ = 31449600. Its totient is φ = 19535328.

The previous prime is 25121539. The next prime is 25121581. The reversal of 25121551 is 15512152.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 25121551 - 2⁵ = 25121519 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25121521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3030 + ... + 7708.

It is an arithmetic number, because the mean of its divisors is an integer number (1965600).

Almost surely, 2^25121551 is an apocalyptic number.

25121551 is a deficient number, since it is larger than the sum of its proper divisors (6328049).

25121551 is a wasteful number, since it uses less digits than its factorization.

25121551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4758.

The product of its digits is 500, while the sum is 22.

The square root of 25121551 is about 5012.1403611631. The cubic root of 25121551 is about 292.8748975723.

The spelling of 25121551 in words is "twenty-five million, one hundred twenty-one thousand, five hundred fifty-one".