1198880261 has 4 divisors (see below), whose sum is σ = 1198960224. Its totient is φ = 1198800300.

The previous prime is 1198880233. The next prime is 1198880269. The reversal of 1198880261 is 1620888911.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1198880261 - 2⁶ = 1198880197 is a prime.

It is a deceptive number, since it divides R_1198880260.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1198880269) 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, 9995 + ... + 49976.

It is an arithmetic number, because the mean of its divisors is an integer number (299740056).

It is a Poulet number, since it divides 2^1198880260-1.

Almost surely, 2^1198880261 is an apocalyptic number.

1198880261 is the 19991-st octagonal number.

It is an amenable number.

1198880261 is a deficient number, since it is larger than the sum of its proper divisors (79963).

1198880261 is an equidigital number, since it uses as much as digits as its factorization.

1198880261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79962.

The product of its (nonzero) digits is 55296, while the sum is 44.

The square root of 1198880261 is about 34624.8503390267. The cubic root of 1198880261 is about 1062.3279384769.

The spelling of 1198880261 in words is "one billion, one hundred ninety-eight million, eight hundred eighty thousand, two hundred sixty-one".