1881425621 has 2 divisors, whose sum is σ = 1881425622. Its totient is φ = 1881425620.

The previous prime is 1881425603. The next prime is 1881425647. The reversal of 1881425621 is 1265241881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1203396100 + 678029521 = 34690^2 + 26039^2 .

It is a cyclic number.

It is not a de Polignac number, because 1881425621 - 2¹⁸ = 1881163477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1881424621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 940712810 + 940712811.

It is an arithmetic number, because the mean of its divisors is an integer number (940712811).

Almost surely, 2^1881425621 is an apocalyptic number.

It is an amenable number.

1881425621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1881425621 is an equidigital number, since it uses as much as digits as its factorization.

1881425621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30720, while the sum is 38.

The square root of 1881425621 is about 43375.4034102278. The cubic root of 1881425621 is about 1234.5130483653.

The spelling of 1881425621 in words is "one billion, eight hundred eighty-one million, four hundred twenty-five thousand, six hundred twenty-one".