921808469 has 2 divisors, whose sum is σ = 921808470. Its totient is φ = 921808468.

The previous prime is 921808457. The next prime is 921808519. The reversal of 921808469 is 964808129.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 679227844 + 242580625 = 26062^2 + 15575^2 .

It is an emirp because it is prime and its reverse (964808129) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-921808469 is a prime.

It is a super-2 number, since 2×921808469² = 1699461707040247922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (921808429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460904234 + 460904235.

It is an arithmetic number, because the mean of its divisors is an integer number (460904235).

Almost surely, 2^921808469 is an apocalyptic number.

It is an amenable number.

921808469 is a deficient number, since it is larger than the sum of its proper divisors (1).

921808469 is an equidigital number, since it uses as much as digits as its factorization.

921808469 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 248832, while the sum is 47.

The square root of 921808469 is about 30361.2988687902. The cubic root of 921808469 is about 973.2256905287.

The spelling of 921808469 in words is "nine hundred twenty-one million, eight hundred eight thousand, four hundred sixty-nine".