19961099 has 2 divisors, whose sum is σ = 19961100. Its totient is φ = 19961098.

The previous prime is 19961069. The next prime is 19961101. The reversal of 19961099 is 99016991.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19961099 - 2²⁴ = 3183883 is a prime.

It is a Sophie Germain prime.

Together with 19961101, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19961059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9980549 + 9980550.

It is an arithmetic number, because the mean of its divisors is an integer number (9980550).

Almost surely, 2^19961099 is an apocalyptic number.

19961099 is a deficient number, since it is larger than the sum of its proper divisors (1).

19961099 is an equidigital number, since it uses as much as digits as its factorization.

19961099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 39366, while the sum is 44.

The square root of 19961099 is about 4467.7845740367. The cubic root of 19961099 is about 271.2656581672.

The spelling of 19961099 in words is "nineteen million, nine hundred sixty-one thousand, ninety-nine".