1221907 has 2 divisors, whose sum is σ = 1221908. Its totient is φ = 1221906.

The previous prime is 1221863. The next prime is 1221917. The reversal of 1221907 is 7091221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221907 - 2¹¹ = 1219859 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610953 + 610954.

It is an arithmetic number, because the mean of its divisors is an integer number (610954).

2^1221907 is an apocalyptic number.

1221907 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221907 is an equidigital number, since it uses as much as digits as its factorization.

1221907 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 252, while the sum is 22.

The square root of 1221907 is about 1105.3990229777. The cubic root of 1221907 is about 106.9086185177.

The spelling of 1221907 in words is "one million, two hundred twenty-one thousand, nine hundred seven".