25423021 has 8 divisors (see below), whose sum is σ = 27662264. Its totient is φ = 23224320.

The previous prime is 25423009. The next prime is 25423043. The reversal of 25423021 is 12032452.

It can be written as a sum of positive squares in 4 ways, for example, as 1550025 + 23872996 = 1245^2 + 4886^2 .

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

It is a 7-Lehmer number, since φ(25423021) divides (25423021-1)⁷.

It is a cyclic number.

It is not a de Polignac number, because 25423021 - 2⁵ = 25422989 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25423021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25423001) 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, 8820 + ... + 11341.

It is an arithmetic number, because the mean of its divisors is an integer number (3457783).

Almost surely, 2^25423021 is an apocalyptic number.

It is an amenable number.

25423021 is a deficient number, since it is larger than the sum of its proper divisors (2239243).

25423021 is a wasteful number, since it uses less digits than its factorization.

25423021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20271.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 25423021 is about 5042.1246513747. The cubic root of 25423021 is about 294.0417860609.

Adding to 25423021 its reverse (12032452), we get a palindrome (37455473).

The spelling of 25423021 in words is "twenty-five million, four hundred twenty-three thousand, twenty-one".