891988073 has 2 divisors, whose sum is σ = 891988074. Its totient is φ = 891988072.

The previous prime is 891988067. The next prime is 891988133. The reversal of 891988073 is 370889198.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 499433104 + 392554969 = 22348^2 + 19813^2 .

It is a cyclic number.

It is not a de Polignac number, because 891988073 - 2¹⁸ = 891725929 is a prime.

It is not a weakly prime, because it can be changed into another prime (891988063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 445994036 + 445994037.

It is an arithmetic number, because the mean of its divisors is an integer number (445994037).

Almost surely, 2^891988073 is an apocalyptic number.

It is an amenable number.

891988073 is a deficient number, since it is larger than the sum of its proper divisors (1).

891988073 is an equidigital number, since it uses as much as digits as its factorization.

891988073 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 870912, while the sum is 53.

The square root of 891988073 is about 29866.1693727200. The cubic root of 891988073 is about 962.6158665933.

The spelling of 891988073 in words is "eight hundred ninety-one million, nine hundred eighty-eight thousand, seventy-three".