1211238916969 has 27 divisors (see below), whose sum is σ = 1319663010981. Its totient is φ = 1111480584960.

The previous prime is 1211238916957. The next prime is 1211238916981. The reversal of 1211238916969 is 9696198321121.

The square root of 1211238916969 is 1100563.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (1211238916957) and next prime (1211238916981).

It can be written as a sum of positive squares in 4 ways, for example, as 85331173225 + 1125907743744 = 292115^2 + 1061088^2 .

It is not a de Polignac number, because 1211238916969 - 2¹⁹ = 1211238392681 is a prime.

It is a super-2 number, since 2×1211238916969² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211238916919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 767091622 + ... + 767093200.

Almost surely, 2^{1211238916969} is an apocalyptic number.

1211238916969 is the 1100563-rd square number.

1211238916969 is the 550282-nd centered octagonal number.

It is an amenable number.

1211238916969 is a deficient number, since it is larger than the sum of its proper divisors (108424094012).

1211238916969 is an frugal number, since it uses more digits than its factorization.

1211238916969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3274 (or 1637 counting only the distinct ones).

The product of its digits is 2519424, while the sum is 58.

The spelling of 1211238916969 in words is "one trillion, two hundred eleven billion, two hundred thirty-eight million, nine hundred sixteen thousand, nine hundred sixty-nine".