1899610561 has 2 divisors, whose sum is σ = 1899610562. Its totient is φ = 1899610560.

The previous prime is 1899610553. The next prime is 1899610621. The reversal of 1899610561 is 1650169981.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1549209600 + 350400961 = 39360^2 + 18719^2 .

It is an emirp because it is prime and its reverse (1650169981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1899610561 - 2³ = 1899610553 is a prime.

It is not a weakly prime, because it can be changed into another prime (1899610541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 949805280 + 949805281.

It is an arithmetic number, because the mean of its divisors is an integer number (949805281).

Almost surely, 2^1899610561 is an apocalyptic number.

It is an amenable number.

1899610561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1899610561 is an equidigital number, since it uses as much as digits as its factorization.

1899610561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 116640, while the sum is 46.

The square root of 1899610561 is about 43584.5220347774. The cubic root of 1899610561 is about 1238.4777020102.

The spelling of 1899610561 in words is "one billion, eight hundred ninety-nine million, six hundred ten thousand, five hundred sixty-one".