24525643921 has 2 divisors, whose sum is σ = 24525643922. Its totient is φ = 24525643920.

The previous prime is 24525643907. The next prime is 24525643949. The reversal of 24525643921 is 12934652542.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23372294400 + 1153349521 = 152880^2 + 33961^2 .

It is a cyclic number.

It is not a de Polignac number, because 24525643921 - 2⁹ = 24525643409 is a prime.

It is not a weakly prime, because it can be changed into another prime (24525643951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12262821960 + 12262821961.

It is an arithmetic number, because the mean of its divisors is an integer number (12262821961).

Almost surely, 2^24525643921 is an apocalyptic number.

It is an amenable number.

24525643921 is a deficient number, since it is larger than the sum of its proper divisors (1).

24525643921 is an equidigital number, since it uses as much as digits as its factorization.

24525643921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 518400, while the sum is 43.

The spelling of 24525643921 in words is "twenty-four billion, five hundred twenty-five million, six hundred forty-three thousand, nine hundred twenty-one".