1608214921 has 4 divisors (see below), whose sum is σ = 1645615312. Its totient is φ = 1570814532.

The previous prime is 1608214913. The next prime is 1608214957. The reversal of 1608214921 is 1294128061.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1608214921 - 2³ = 1608214913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1608214991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18700131 + ... + 18700216.

It is an arithmetic number, because the mean of its divisors is an integer number (411403828).

Almost surely, 2^1608214921 is an apocalyptic number.

It is an amenable number.

1608214921 is a deficient number, since it is larger than the sum of its proper divisors (37400391).

1608214921 is an equidigital number, since it uses as much as digits as its factorization.

1608214921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37400390.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 1608214921 is about 40102.5550432887. Note that the first 3 decimals coincide. The cubic root of 1608214921 is about 1171.6053937657.

The spelling of 1608214921 in words is "one billion, six hundred eight million, two hundred fourteen thousand, nine hundred twenty-one".