1191671563 has 2 divisors, whose sum is σ = 1191671564. Its totient is φ = 1191671562.

The previous prime is 1191671549. The next prime is 1191671573. The reversal of 1191671563 is 3651761911.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1191671563 - 2⁵ = 1191671531 is a prime.

It is a super-2 number, since 2×1191671563² = 2840162228125725938, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1191671573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 595835781 + 595835782.

It is an arithmetic number, because the mean of its divisors is an integer number (595835782).

Almost surely, 2^1191671563 is an apocalyptic number.

1191671563 is a deficient number, since it is larger than the sum of its proper divisors (1).

1191671563 is an equidigital number, since it uses as much as digits as its factorization.

1191671563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34020, while the sum is 40.

The square root of 1191671563 is about 34520.5962144341. The cubic root of 1191671563 is about 1060.1944472403.

The spelling of 1191671563 in words is "one billion, one hundred ninety-one million, six hundred seventy-one thousand, five hundred sixty-three".