1211993969 has 2 divisors, whose sum is σ = 1211993970. Its totient is φ = 1211993968.

The previous prime is 1211993963. The next prime is 1211994019. The reversal of 1211993969 is 9693991121.

It is a happy number.

It is an a-pointer prime, because the next prime (1211994019) can be obtained adding 1211993969 to its sum of digits (50).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1173405025 + 38588944 = 34255^2 + 6212^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1211993969 is a prime.

It is a super-2 number, since 2×1211993969² = 2937858761784745922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1211993963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605996984 + 605996985.

It is an arithmetic number, because the mean of its divisors is an integer number (605996985).

Almost surely, 2^1211993969 is an apocalyptic number.

It is an amenable number.

1211993969 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211993969 is an equidigital number, since it uses as much as digits as its factorization.

1211993969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 236196, while the sum is 50.

The square root of 1211993969 is about 34813.7037529764. The cubic root of 1211993969 is about 1066.1872537769.

The spelling of 1211993969 in words is "one billion, two hundred eleven million, nine hundred ninety-three thousand, nine hundred sixty-nine".