19911413 has 2 divisors, whose sum is σ = 19911414. Its totient is φ = 19911412.

The previous prime is 19911389. The next prime is 19911431. The reversal of 19911413 is 31411991.

Together with next prime (19911431) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16459249 + 3452164 = 4057^2 + 1858^2 .

It is a cyclic number.

It is not a de Polignac number, because 19911413 - 2⁶ = 19911349 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19911473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9955706 + 9955707.

It is an arithmetic number, because the mean of its divisors is an integer number (9955707).

Almost surely, 2^19911413 is an apocalyptic number.

It is an amenable number.

19911413 is a deficient number, since it is larger than the sum of its proper divisors (1).

19911413 is an equidigital number, since it uses as much as digits as its factorization.

19911413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 972, while the sum is 29.

The square root of 19911413 is about 4462.2206355132. The cubic root of 19911413 is about 271.0403982930.

The spelling of 19911413 in words is "nineteen million, nine hundred eleven thousand, four hundred thirteen".