189075721 has 2 divisors, whose sum is σ = 189075722. Its totient is φ = 189075720.

The previous prime is 189075703. The next prime is 189075749. The reversal of 189075721 is 127570981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 113124496 + 75951225 = 10636^2 + 8715^2 .

It is a cyclic number.

It is not a de Polignac number, because 189075721 - 2⁹ = 189075209 is a prime.

It is not a weakly prime, because it can be changed into another prime (189075701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94537860 + 94537861.

It is an arithmetic number, because the mean of its divisors is an integer number (94537861).

Almost surely, 2^189075721 is an apocalyptic number.

It is an amenable number.

189075721 is a deficient number, since it is larger than the sum of its proper divisors (1).

189075721 is an equidigital number, since it uses as much as digits as its factorization.

189075721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 35280, while the sum is 40.

The square root of 189075721 is about 13750.4807552318. The cubic root of 189075721 is about 573.9559843144.

The spelling of 189075721 in words is "one hundred eighty-nine million, seventy-five thousand, seven hundred twenty-one".