1211011111987 has 8 divisors (see below), whose sum is σ = 1218727862352. Its totient is φ = 1203305637600.

The previous prime is 1211011111967. The next prime is 1211011111991. The reversal of 1211011111987 is 7891111101121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1211011111987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211011111957) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2603464 + ... + 3033157.

It is an arithmetic number, because the mean of its divisors is an integer number (152340982794).

Almost surely, 2^{1211011111987} is an apocalyptic number.

1211011111987 is a deficient number, since it is larger than the sum of its proper divisors (7716750365).

1211011111987 is a wasteful number, since it uses less digits than its factorization.

1211011111987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5637989.

The product of its (nonzero) digits is 1008, while the sum is 34.

The spelling of 1211011111987 in words is "one trillion, two hundred eleven billion, eleven million, one hundred eleven thousand, nine hundred eighty-seven".