1211879334555 has 24 divisors (see below), whose sum is σ = 2117130941952. Its totient is φ = 641246385024.

The previous prime is 1211879334493. The next prime is 1211879334581. The reversal of 1211879334555 is 5554339781121.

It is a happy number.

1211879334555 is a `hidden beast` number, since 1 + 2 + 1 + 1 + 87 + 9 + 3 + 3 + 4 + 555 = 666.

It is not a de Polignac number, because 1211879334555 - 2²³ = 1211870945947 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 106020474 + ... + 106031903.

It is an arithmetic number, because the mean of its divisors is an integer number (88213789248).

Almost surely, 2^{1211879334555} is an apocalyptic number.

1211879334555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1211879334555 is a deficient number, since it is larger than the sum of its proper divisors (905251607397).

1211879334555 is a wasteful number, since it uses less digits than its factorization.

1211879334555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212052515 (or 212052512 counting only the distinct ones).

The product of its digits is 4536000, while the sum is 54.

The spelling of 1211879334555 in words is "one trillion, two hundred eleven billion, eight hundred seventy-nine million, three hundred thirty-four thousand, five hundred fifty-five".