1187186520691 has 6 divisors (see below), whose sum is σ = 1249675021140. Its totient is φ = 1124698520196.

The previous prime is 1187186520671. The next prime is 1187186520701. The reversal of 1187186520691 is 1960256817811.

It is not a de Polignac number, because 1187186520691 - 2¹⁵ = 1187186487923 is a prime.

It is a super-2 number, since 2×1187186520691² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1187186520661) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4624390 + ... + 4874356.

It is an arithmetic number, because the mean of its divisors is an integer number (208279170190).

Almost surely, 2^{1187186520691} is an apocalyptic number.

1187186520691 is a deficient number, since it is larger than the sum of its proper divisors (62488500449).

1187186520691 is an frugal number, since it uses more digits than its factorization.

1187186520691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499953 (or 249986 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 55.

The spelling of 1187186520691 in words is "one trillion, one hundred eighty-seven billion, one hundred eighty-six million, five hundred twenty thousand, six hundred ninety-one".