1881630689 has 2 divisors, whose sum is σ = 1881630690. Its totient is φ = 1881630688.

The previous prime is 1881630643. The next prime is 1881630727. The reversal of 1881630689 is 9860361881.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1737222400 + 144408289 = 41680^2 + 12017^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1881630689 is a prime.

It is a super-2 number, since 2×1881630689² = 7081068099573229442, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1881630889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 940815344 + 940815345.

It is an arithmetic number, because the mean of its divisors is an integer number (940815345).

Almost surely, 2^1881630689 is an apocalyptic number.

It is an amenable number.

1881630689 is a deficient number, since it is larger than the sum of its proper divisors (1).

1881630689 is an equidigital number, since it uses as much as digits as its factorization.

1881630689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 497664, while the sum is 50.

The square root of 1881630689 is about 43377.7672200864. The cubic root of 1881630689 is about 1234.5578990930.

The spelling of 1881630689 in words is "one billion, eight hundred eighty-one million, six hundred thirty thousand, six hundred eighty-nine".