1111157381 has 2 divisors, whose sum is σ = 1111157382. Its totient is φ = 1111157380.

The previous prime is 1111157339. The next prime is 1111157387. The reversal of 1111157381 is 1837511111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 566868481 + 544288900 = 23809^2 + 23330^2 .

It is an emirp because it is prime and its reverse (1837511111) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1111157381 - 2¹⁰ = 1111156357 is a prime.

It is a super-2 number, since 2×1111157381² = 2469341450701558322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1111157387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 555578690 + 555578691.

It is an arithmetic number, because the mean of its divisors is an integer number (555578691).

Almost surely, 2^1111157381 is an apocalyptic number.

It is an amenable number.

1111157381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1111157381 is an equidigital number, since it uses as much as digits as its factorization.

1111157381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 840, while the sum is 29.

The square root of 1111157381 is about 33334.0273744413. The cubic root of 1111157381 is about 1035.7585455820.

Adding to 1111157381 its reverse (1837511111), we get a palindrome (2948668492).

The spelling of 1111157381 in words is "one billion, one hundred eleven million, one hundred fifty-seven thousand, three hundred eighty-one".