121312811 has 2 divisors, whose sum is σ = 121312812. Its totient is φ = 121312810.

The previous prime is 121312783. The next prime is 121312861. The reversal of 121312811 is 118213121.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121312811 - 2⁶ = 121312747 is a prime.

It is a super-2 number, since 2×121312811² = 29433596225443442, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (121312861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60656405 + 60656406.

It is an arithmetic number, because the mean of its divisors is an integer number (60656406).

Almost surely, 2^121312811 is an apocalyptic number.

121312811 is a deficient number, since it is larger than the sum of its proper divisors (1).

121312811 is an equidigital number, since it uses as much as digits as its factorization.

121312811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 96, while the sum is 20.

The square root of 121312811 is about 11014.2095040906. The cubic root of 121312811 is about 495.0346008531.

Adding to 121312811 its reverse (118213121), we get a palindrome (239525932).

The spelling of 121312811 in words is "one hundred twenty-one million, three hundred twelve thousand, eight hundred eleven".