1211199971 has 2 divisors, whose sum is σ = 1211199972. Its totient is φ = 1211199970.

The previous prime is 1211199953. The next prime is 1211200009. The reversal of 1211199971 is 1799911121.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1211199971 - 2²⁶ = 1144091107 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211199271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605599985 + 605599986.

It is an arithmetic number, because the mean of its divisors is an integer number (605599986).

Almost surely, 2^1211199971 is an apocalyptic number.

1211199971 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211199971 is an equidigital number, since it uses as much as digits as its factorization.

1211199971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10206, while the sum is 41.

The square root of 1211199971 is about 34802.2983580108. The cubic root of 1211199971 is about 1065.9543770742.

The spelling of 1211199971 in words is "one billion, two hundred eleven million, one hundred ninety-nine thousand, nine hundred seventy-one".