1694021221 has 8 divisors (see below), whose sum is σ = 1702534400. Its totient is φ = 1685529648.

The previous prime is 1694021213. The next prime is 1694021237. The reversal of 1694021221 is 1221204961.

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 1694021221 - 2³ = 1694021213 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1694021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1694021201) by changing a digit.

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, 164980 + ... + 174946.

It is an arithmetic number, because the mean of its divisors is an integer number (212816800).

Almost surely, 2^1694021221 is an apocalyptic number.

It is an amenable number.

1694021221 is a deficient number, since it is larger than the sum of its proper divisors (8513179).

1694021221 is an equidigital number, since it uses as much as digits as its factorization.

1694021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10803.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 1694021221 is about 41158.4890514703. The cubic root of 1694021221 is about 1192.0824166867.

The spelling of 1694021221 in words is "one billion, six hundred ninety-four million, twenty-one thousand, two hundred twenty-one".