25770021 has 8 divisors (see below), whose sum is σ = 35468544. Its totient is φ = 16625760.

The previous prime is 25770013. The next prime is 25770071. The reversal of 25770021 is 12007752.

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

It is not a de Polignac number, because 25770021 - 2³ = 25770013 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 25769973 and 25770000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25770071) 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, 138456 + ... + 138641.

It is an arithmetic number, because the mean of its divisors is an integer number (4433568).

Almost surely, 2^25770021 is an apocalyptic number.

It is an amenable number.

25770021 is a deficient number, since it is larger than the sum of its proper divisors (9698523).

25770021 is a wasteful number, since it uses less digits than its factorization.

25770021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277131.

The product of its (nonzero) digits is 980, while the sum is 24.

The square root of 25770021 is about 5076.4181269868. The cubic root of 25770021 is about 295.3735419349.

Adding to 25770021 its reverse (12007752), we get a palindrome (37777773).

The spelling of 25770021 in words is "twenty-five million, seven hundred seventy thousand, twenty-one".