1211561864149 has 32 divisors (see below), whose sum is σ = 1540419485696. Its totient is φ = 926973927360.

The previous prime is 1211561864069. The next prime is 1211561864173. The reversal of 1211561864149 is 9414681651121.

It is not a de Polignac number, because 1211561864149 - 2⁷ = 1211561864021 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211561861149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3581644 + ... + 3905290.

It is an arithmetic number, because the mean of its divisors is an integer number (48138108928).

Almost surely, 2^{1211561864149} is an apocalyptic number.

It is an amenable number.

1211561864149 is a deficient number, since it is larger than the sum of its proper divisors (328857621547).

1211561864149 is a wasteful number, since it uses less digits than its factorization.

1211561864149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325025.

The product of its digits is 414720, while the sum is 49.

The spelling of 1211561864149 in words is "one trillion, two hundred eleven billion, five hundred sixty-one million, eight hundred sixty-four thousand, one hundred forty-nine".