919210421 has 2 divisors, whose sum is σ = 919210422. Its totient is φ = 919210420.

The previous prime is 919210399. The next prime is 919210427. The reversal of 919210421 is 124012919.

919210421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 678029521 + 241180900 = 26039^2 + 15530^2 .

It is an emirp because it is prime and its reverse (124012919) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 919210421 - 2¹⁴ = 919194037 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 (919210427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 459605210 + 459605211.

It is an arithmetic number, because the mean of its divisors is an integer number (459605211).

Almost surely, 2^919210421 is an apocalyptic number.

It is an amenable number.

919210421 is a deficient number, since it is larger than the sum of its proper divisors (1).

919210421 is an equidigital number, since it uses as much as digits as its factorization.

919210421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 919210421 is about 30318.4831579682. The cubic root of 919210421 is about 972.3105090057.

The spelling of 919210421 in words is "nine hundred nineteen million, two hundred ten thousand, four hundred twenty-one".