1197866881 has 4 divisors (see below), whose sum is σ = 1198988500. Its totient is φ = 1196745264.

The previous prime is 1197866861. The next prime is 1197866893. The reversal of 1197866881 is 1886687911.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1886687911 = 36691 ⋅51421.

It can be written as a sum of positive squares in 2 ways, for example, as 267616881 + 930250000 = 16359^2 + 30500^2 .

It is a cyclic number.

It is not a de Polignac number, because 1197866881 - 2¹⁹ = 1197342593 is a prime.

It is a super-2 number, since 2×1197866881² = 2869770129193336322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1197866851) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 559206 + ... + 561343.

It is an arithmetic number, because the mean of its divisors is an integer number (299747125).

Almost surely, 2^1197866881 is an apocalyptic number.

It is an amenable number.

1197866881 is a deficient number, since it is larger than the sum of its proper divisors (1121619).

1197866881 is a wasteful number, since it uses less digits than its factorization.

1197866881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1121618.

The product of its digits is 1161216, while the sum is 55.

The square root of 1197866881 is about 34610.2135358914. The cubic root of 1197866881 is about 1062.0285353902.

The spelling of 1197866881 in words is "one billion, one hundred ninety-seven million, eight hundred sixty-six thousand, eight hundred eighty-one".