25533782021 has 4 divisors (see below), whose sum is σ = 27855034944. Its totient is φ = 23212529100.

The previous prime is 25533781993. The next prime is 25533782041. The reversal of 25533782021 is 12028733552.

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 25533782021 - 2⁶ = 25533781957 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25533782041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1160626445 + ... + 1160626466.

It is an arithmetic number, because the mean of its divisors is an integer number (6963758736).

Almost surely, 2^25533782021 is an apocalyptic number.

It is an amenable number.

25533782021 is a deficient number, since it is larger than the sum of its proper divisors (2321252923).

25533782021 is a wasteful number, since it uses less digits than its factorization.

25533782021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2321252922.

The product of its (nonzero) digits is 100800, while the sum is 38.

The spelling of 25533782021 in words is "twenty-five billion, five hundred thirty-three million, seven hundred eighty-two thousand, twenty-one".