1187117251 has 4 divisors (see below), whose sum is σ = 1187329912. Its totient is φ = 1186904592.

The previous prime is 1187117249. The next prime is 1187117263. The reversal of 1187117251 is 1527117811.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1187117251 - 2¹ = 1187117249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1187117201) 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, 97725 + ... + 109198.

It is an arithmetic number, because the mean of its divisors is an integer number (296832478).

Almost surely, 2^1187117251 is an apocalyptic number.

1187117251 is a deficient number, since it is larger than the sum of its proper divisors (212661).

1187117251 is an equidigital number, since it uses as much as digits as its factorization.

1187117251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212660.

The product of its digits is 3920, while the sum is 34.

The square root of 1187117251 is about 34454.5679264738. The cubic root of 1187117251 is about 1058.8421114000.

The spelling of 1187117251 in words is "one billion, one hundred eighty-seven million, one hundred seventeen thousand, two hundred fifty-one".