919351021 has 2 divisors, whose sum is σ = 919351022. Its totient is φ = 919351020.

The previous prime is 919351001. The next prime is 919351033. The reversal of 919351021 is 120153919.

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., 638118121 + 281232900 = 25261^2 + 16770^2 .

It is an emirp because it is prime and its reverse (120153919) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 919351021 - 2⁵ = 919350989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (919351001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 459675510 + 459675511.

It is an arithmetic number, because the mean of its divisors is an integer number (459675511).

Almost surely, 2^919351021 is an apocalyptic number.

It is an amenable number.

919351021 is a deficient number, since it is larger than the sum of its proper divisors (1).

919351021 is an equidigital number, since it uses as much as digits as its factorization.

919351021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2430, while the sum is 31.

The square root of 919351021 is about 30320.8017868921. The cubic root of 919351021 is about 972.3600804948.

The spelling of 919351021 in words is "nine hundred nineteen million, three hundred fifty-one thousand, twenty-one".