1155001997 has 2 divisors, whose sum is σ = 1155001998. Its totient is φ = 1155001996.

The previous prime is 1155001919. The next prime is 1155002003. The reversal of 1155001997 is 7991005511.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1078071556 + 76930441 = 32834^2 + 8771^2 .

It is an emirp because it is prime and its reverse (7991005511) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1155001997 is a prime.

It is a super-2 number, since 2×1155001997² = 2668059226147976018, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1155001997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1155001597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 577500998 + 577500999.

It is an arithmetic number, because the mean of its divisors is an integer number (577500999).

Almost surely, 2^1155001997 is an apocalyptic number.

It is an amenable number.

1155001997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1155001997 is an equidigital number, since it uses as much as digits as its factorization.

1155001997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14175, while the sum is 38.

The square root of 1155001997 is about 33985.3203162777. The cubic root of 1155001997 is about 1049.2063532557.

The spelling of 1155001997 in words is "one billion, one hundred fifty-five million, one thousand, nine hundred ninety-seven".