187825609921 has 2 divisors, whose sum is σ = 187825609922. Its totient is φ = 187825609920.

The previous prime is 187825609903. The next prime is 187825609927. The reversal of 187825609921 is 129906528781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 119879367696 + 67946242225 = 346236^2 + 260665^2 .

It is a cyclic number.

It is not a de Polignac number, because 187825609921 - 2⁵ = 187825609889 is a prime.

It is not a weakly prime, because it can be changed into another prime (187825609927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93912804960 + 93912804961.

It is an arithmetic number, because the mean of its divisors is an integer number (93912804961).

Almost surely, 2^187825609921 is an apocalyptic number.

It is an amenable number.

187825609921 is a deficient number, since it is larger than the sum of its proper divisors (1).

187825609921 is an equidigital number, since it uses as much as digits as its factorization.

187825609921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4354560, while the sum is 58.

The spelling of 187825609921 in words is "one hundred eighty-seven billion, eight hundred twenty-five million, six hundred nine thousand, nine hundred twenty-one".