1970921 has 2 divisors, whose sum is σ = 1970922. Its totient is φ = 1970920.

The previous prime is 1970873. The next prime is 1970923. The reversal of 1970921 is 1290791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1755625 + 215296 = 1325^2 + 464^2 .

It is an emirp because it is prime and its reverse (1290791) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1970921 is a prime.

Together with 1970923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1970923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 985460 + 985461.

It is an arithmetic number, because the mean of its divisors is an integer number (985461).

2^1970921 is an apocalyptic number.

It is an amenable number.

1970921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1970921 is an equidigital number, since it uses as much as digits as its factorization.

1970921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1134, while the sum is 29.

The square root of 1970921 is about 1403.8949390891. The cubic root of 1970921 is about 125.3785007407.

The spelling of 1970921 in words is "one million, nine hundred seventy thousand, nine hundred twenty-one".