1011211997 has 4 divisors (see below), whose sum is σ = 1055177760. Its totient is φ = 967246236.

The previous prime is 1011211979. The next prime is 1011212011. The reversal of 1011211997 is 7991121101.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7991121101 = 13249 ⋅603149.

It is a cyclic number.

It is not a de Polignac number, because 1011211997 - 2¹⁰ = 1011210973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011211937) 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 3 ways as a sum of consecutive naturals, for example, 21982847 + ... + 21982892.

It is an arithmetic number, because the mean of its divisors is an integer number (263794440).

Almost surely, 2^1011211997 is an apocalyptic number.

It is an amenable number.

1011211997 is a deficient number, since it is larger than the sum of its proper divisors (43965763).

1011211997 is an equidigital number, since it uses as much as digits as its factorization.

1011211997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43965762.

The product of its (nonzero) digits is 1134, while the sum is 32.

The square root of 1011211997 is about 31799.5596982097. The cubic root of 1011211997 is about 1003.7234510383.

The spelling of 1011211997 in words is "one billion, eleven million, two hundred eleven thousand, nine hundred ninety-seven".