1192990861 has 4 divisors (see below), whose sum is σ = 1263166812. Its totient is φ = 1122814912.

The previous prime is 1192990831. The next prime is 1192990901. The reversal of 1192990861 is 1680992911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1680992911 = 13 ⋅129307147.

It can be written as a sum of positive squares in 2 ways, for example, as 965282761 + 227708100 = 31069^2 + 15090^2 .

It is not a de Polignac number, because 1192990861 - 2²⁵ = 1159436429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1192990831) 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, 35087950 + ... + 35087983.

It is an arithmetic number, because the mean of its divisors is an integer number (315791703).

Almost surely, 2^1192990861 is an apocalyptic number.

It is an amenable number.

1192990861 is a deficient number, since it is larger than the sum of its proper divisors (70175951).

1192990861 is an equidigital number, since it uses as much as digits as its factorization.

1192990861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70175950.

The product of its (nonzero) digits is 69984, while the sum is 46.

The square root of 1192990861 is about 34539.6997815557. The cubic root of 1192990861 is about 1060.5855495663.

The spelling of 1192990861 in words is "one billion, one hundred ninety-two million, nine hundred ninety thousand, eight hundred sixty-one".