1654921 has 2 divisors, whose sum is σ = 1654922. Its totient is φ = 1654920.

The previous prime is 1654903. The next prime is 1654931. The reversal of 1654921 is 1294561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1071225 + 583696 = 1035^2 + 764^2 .

It is an emirp because it is prime and its reverse (1294561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1654921 - 2⁵ = 1654889 is a prime.

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 1654921.

It is not a weakly prime, because it can be changed into another prime (1654931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 827460 + 827461.

It is an arithmetic number, because the mean of its divisors is an integer number (827461).

2^1654921 is an apocalyptic number.

It is an amenable number.

1654921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1654921 is an equidigital number, since it uses as much as digits as its factorization.

1654921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 28.

The square root of 1654921 is about 1286.4373284385. The cubic root of 1654921 is about 118.2839327398.

The spelling of 1654921 in words is "one million, six hundred fifty-four thousand, nine hundred twenty-one".