1121779457 has 2 divisors, whose sum is σ = 1121779458. Its totient is φ = 1121779456.

The previous prime is 1121779411. The next prime is 1121779469. The reversal of 1121779457 is 7549771211.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 977875441 + 143904016 = 31271^2 + 11996^2 .

It is an emirp because it is prime and its reverse (7549771211) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1121779457 - 2²² = 1117585153 is a prime.

It is not a weakly prime, because it can be changed into another prime (1121779157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 560889728 + 560889729.

It is an arithmetic number, because the mean of its divisors is an integer number (560889729).

Almost surely, 2^1121779457 is an apocalyptic number.

It is an amenable number.

1121779457 is a deficient number, since it is larger than the sum of its proper divisors (1).

1121779457 is an equidigital number, since it uses as much as digits as its factorization.

1121779457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 123480, while the sum is 44.

The square root of 1121779457 is about 33492.9762338315. The cubic root of 1121779457 is about 1039.0485186369.

The spelling of 1121779457 in words is "one billion, one hundred twenty-one million, seven hundred seventy-nine thousand, four hundred fifty-seven".