19629661 has 2 divisors, whose sum is σ = 19629662. Its totient is φ = 19629660.

The previous prime is 19629619. The next prime is 19629667. The reversal of 19629661 is 16692691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19624900 + 4761 = 4430^2 + 69^2 .

It is a cyclic number.

It is not a de Polignac number, because 19629661 - 2⁹ = 19629149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19629667) 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, 9814830 + 9814831.

It is an arithmetic number, because the mean of its divisors is an integer number (9814831).

Almost surely, 2^19629661 is an apocalyptic number.

It is an amenable number.

19629661 is a deficient number, since it is larger than the sum of its proper divisors (1).

19629661 is an equidigital number, since it uses as much as digits as its factorization.

19629661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992, while the sum is 40.

The square root of 19629661 is about 4430.5373263296. The cubic root of 19629661 is about 269.7558881855.

The spelling of 19629661 in words is "nineteen million, six hundred twenty-nine thousand, six hundred sixty-one".