2190171649 has 2 divisors, whose sum is σ = 2190171650. Its totient is φ = 2190171648.

The previous prime is 2190171647. The next prime is 2190171671. The reversal of 2190171649 is 9461710912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1769716624 + 420455025 = 42068^2 + 20505^2 .

It is a cyclic number.

It is not a de Polignac number, because 2190171649 - 2¹ = 2190171647 is a prime.

Together with 2190171647, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (2190171647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1095085824 + 1095085825.

It is an arithmetic number, because the mean of its divisors is an integer number (1095085825).

Almost surely, 2^2190171649 is an apocalyptic number.

It is an amenable number.

2190171649 is a deficient number, since it is larger than the sum of its proper divisors (1).

2190171649 is an equidigital number, since it uses as much as digits as its factorization.

2190171649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 2190171649 is about 46799.2697485762. The cubic root of 2190171649 is about 1298.6517874774.

The spelling of 2190171649 in words is "two billion, one hundred ninety million, one hundred seventy-one thousand, six hundred forty-nine".