1261152099 has 10 divisors (see below), whose sum is σ = 1883943380. Its totient is φ = 840768012.

The previous prime is 1261152097. The next prime is 1261152107. The reversal of 1261152099 is 9902511621.

1261152099 is a `hidden beast` number, since 12 + 611 + 5 + 20 + 9 + 9 = 666.

It is not a de Polignac number, because 1261152099 - 2¹ = 1261152097 is a prime.

It is a super-3 number, since 3×1261152099³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1261152097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 7784809 + ... + 7784970.

It is an arithmetic number, because the mean of its divisors is an integer number (188394338).

Almost surely, 2^1261152099 is an apocalyptic number.

1261152099 is a deficient number, since it is larger than the sum of its proper divisors (622791281).

1261152099 is an equidigital number, since it uses as much as digits as its factorization.

1261152099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15569791 (or 15569782 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 1261152099 is about 35512.7033468307. The cubic root of 1261152099 is about 1080.4113941975.

The spelling of 1261152099 in words is "one billion, two hundred sixty-one million, one hundred fifty-two thousand, ninety-nine".