188521973 has 2 divisors, whose sum is σ = 188521974. Its totient is φ = 188521972.

The previous prime is 188521937. The next prime is 188521979. The reversal of 188521973 is 379125881.

Together with previous prime (188521937) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139759684 + 48762289 = 11822^2 + 6983^2 .

It is a cyclic number.

It is not a de Polignac number, because 188521973 - 2¹⁴ = 188505589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (188521979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94260986 + 94260987.

It is an arithmetic number, because the mean of its divisors is an integer number (94260987).

Almost surely, 2^188521973 is an apocalyptic number.

It is an amenable number.

188521973 is a deficient number, since it is larger than the sum of its proper divisors (1).

188521973 is an equidigital number, since it uses as much as digits as its factorization.

188521973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 44.

The square root of 188521973 is about 13730.3304038905. The cubic root of 188521973 is about 573.3951194981.

The spelling of 188521973 in words is "one hundred eighty-eight million, five hundred twenty-one thousand, nine hundred seventy-three".