1211217797 has 2 divisors, whose sum is σ = 1211217798. Its totient is φ = 1211217796.

The previous prime is 1211217793. The next prime is 1211217817. The reversal of 1211217797 is 7977121121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 996917476 + 214300321 = 31574^2 + 14639^2 .

It is an emirp because it is prime and its reverse (7977121121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1211217797 - 2² = 1211217793 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211217797.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211217793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605608898 + 605608899.

It is an arithmetic number, because the mean of its divisors is an integer number (605608899).

Almost surely, 2^1211217797 is an apocalyptic number.

It is an amenable number.

1211217797 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211217797 is an equidigital number, since it uses as much as digits as its factorization.

1211217797 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12348, while the sum is 38.

The square root of 1211217797 is about 34802.5544608438. The cubic root of 1211217797 is about 1065.9596064913.

The spelling of 1211217797 in words is "one billion, two hundred eleven million, two hundred seventeen thousand, seven hundred ninety-seven".