25156421 has 4 divisors (see below), whose sum is σ = 25691712. Its totient is φ = 24621132.

The previous prime is 25156393. The next prime is 25156429. The reversal of 25156421 is 12465152.

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 25156421 - 2⁶ = 25156357 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 (25156429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 267575 + ... + 267668.

It is an arithmetic number, because the mean of its divisors is an integer number (6422928).

Almost surely, 2^25156421 is an apocalyptic number.

It is an amenable number.

25156421 is a deficient number, since it is larger than the sum of its proper divisors (535291).

25156421 is an equidigital number, since it uses as much as digits as its factorization.

25156421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 535290.

The product of its digits is 2400, while the sum is 26.

The square root of 25156421 is about 5015.6177087174. The cubic root of 25156421 is about 293.0103433779.

The spelling of 25156421 in words is "twenty-five million, one hundred fifty-six thousand, four hundred twenty-one".