111211221977 has 2 divisors, whose sum is σ = 111211221978. Its totient is φ = 111211221976.

The previous prime is 111211221949. The next prime is 111211222049. The reversal of 111211221977 is 779122112111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 109097429401 + 2113792576 = 330299^2 + 45976^2 .

It is a cyclic number.

It is not a de Polignac number, because 111211221977 - 2²⁴ = 111194444761 is a prime.

It is not a weakly prime, because it can be changed into another prime (111211224977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55605610988 + 55605610989.

It is an arithmetic number, because the mean of its divisors is an integer number (55605610989).

Almost surely, 2^111211221977 is an apocalyptic number.

It is an amenable number.

111211221977 is a deficient number, since it is larger than the sum of its proper divisors (1).

111211221977 is an equidigital number, since it uses as much as digits as its factorization.

111211221977 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3528, while the sum is 35.

The spelling of 111211221977 in words is "one hundred eleven billion, two hundred eleven million, two hundred twenty-one thousand, nine hundred seventy-seven".