1222156787 has 2 divisors, whose sum is σ = 1222156788. Its totient is φ = 1222156786.

The previous prime is 1222156783. The next prime is 1222156813. The reversal of 1222156787 is 7876512221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1222156787 - 2² = 1222156783 is a prime.

It is not a weakly prime, because it can be changed into another prime (1222156783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 611078393 + 611078394.

It is an arithmetic number, because the mean of its divisors is an integer number (611078394).

Almost surely, 2^1222156787 is an apocalyptic number.

1222156787 is a deficient number, since it is larger than the sum of its proper divisors (1).

1222156787 is an equidigital number, since it uses as much as digits as its factorization.

1222156787 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 94080, while the sum is 41.

The square root of 1222156787 is about 34959.3590759327. The cubic root of 1222156787 is about 1069.1590291379.

The spelling of 1222156787 in words is "one billion, two hundred twenty-two million, one hundred fifty-six thousand, seven hundred eighty-seven".