25154521643 has 4 divisors (see below), whose sum is σ = 25163661528. Its totient is φ = 25145381760.

The previous prime is 25154521633. The next prime is 25154521649. The reversal of 25154521643 is 34612545152.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 25154521643 - 2⁸ = 25154521387 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25154521597 and 25154521606.

It is not an unprimeable number, because it can be changed into a prime (25154521649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4565813 + ... + 4571318.

It is an arithmetic number, because the mean of its divisors is an integer number (6290915382).

Almost surely, 2^25154521643 is an apocalyptic number.

25154521643 is a deficient number, since it is larger than the sum of its proper divisors (9139885).

25154521643 is an equidigital number, since it uses as much as digits as its factorization.

25154521643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9139884.

The product of its digits is 144000, while the sum is 38.

The spelling of 25154521643 in words is "twenty-five billion, one hundred fifty-four million, five hundred twenty-one thousand, six hundred forty-three".