19445081 has 2 divisors, whose sum is σ = 19445082. Its totient is φ = 19445080.

The previous prime is 19445071. The next prime is 19445089. The reversal of 19445081 is 18054491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19219456 + 225625 = 4384^2 + 475^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19445081 is a prime.

It is a super-2 number, since 2×19445081² = 756222350193122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19445089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9722540 + 9722541.

It is an arithmetic number, because the mean of its divisors is an integer number (9722541).

Almost surely, 2^19445081 is an apocalyptic number.

It is an amenable number.

19445081 is a deficient number, since it is larger than the sum of its proper divisors (1).

19445081 is an equidigital number, since it uses as much as digits as its factorization.

19445081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 19445081 is about 4409.6576964658. The cubic root of 19445081 is about 268.9077086967.

The spelling of 19445081 in words is "nineteen million, four hundred forty-five thousand, eighty-one".