921006505 has 8 divisors (see below), whose sum is σ = 1143318600. Its totient is φ = 711398016.

The previous prime is 921006491. The next prime is 921006511. The reversal of 921006505 is 505600129.

It can be written as a sum of positive squares in 4 ways, for example, as 393109929 + 527896576 = 19827^2 + 22976^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 921006505 - 2⁹ = 921005993 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3175740 + ... + 3176029.

It is an arithmetic number, because the mean of its divisors is an integer number (142914825).

Almost surely, 2^921006505 is an apocalyptic number.

It is an amenable number.

921006505 is a deficient number, since it is larger than the sum of its proper divisors (222312095).

921006505 is a wasteful number, since it uses less digits than its factorization.

921006505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6351803.

The product of its (nonzero) digits is 2700, while the sum is 28.

The square root of 921006505 is about 30348.0889843166. The cubic root of 921006505 is about 972.9433764894.

The spelling of 921006505 in words is "nine hundred twenty-one million, six thousand, five hundred five".