919249813 has 2 divisors, whose sum is σ = 919249814. Its totient is φ = 919249812.

The previous prime is 919249787. The next prime is 919249819. The reversal of 919249813 is 318942919.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 628103844 + 291145969 = 25062^2 + 17063^2 .

It is an emirp because it is prime and its reverse (318942919) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 919249813 - 2⁵ = 919249781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (919249819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 459624906 + 459624907.

It is an arithmetic number, because the mean of its divisors is an integer number (459624907).

Almost surely, 2^919249813 is an apocalyptic number.

It is an amenable number.

919249813 is a deficient number, since it is larger than the sum of its proper divisors (1).

919249813 is an equidigital number, since it uses as much as digits as its factorization.

919249813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 46.

The square root of 919249813 is about 30319.1327877299. The cubic root of 919249813 is about 972.3243979941.

The spelling of 919249813 in words is "nine hundred nineteen million, two hundred forty-nine thousand, eight hundred thirteen".