1211957354161 has 16 divisors (see below), whose sum is σ = 1277846454528. Its totient is φ = 1147170816000.

The previous prime is 1211957354159. The next prime is 1211957354171. The reversal of 1211957354161 is 1614537591121.

It is not a de Polignac number, because 1211957354161 - 2¹ = 1211957354159 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211957354131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21011761 + ... + 21069361.

It is an arithmetic number, because the mean of its divisors is an integer number (79865403408).

Almost surely, 2^{1211957354161} is an apocalyptic number.

It is an amenable number.

1211957354161 is a deficient number, since it is larger than the sum of its proper divisors (65889100367).

1211957354161 is an equidigital number, since it uses as much as digits as its factorization.

1211957354161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67152.

The product of its digits is 226800, while the sum is 46.

The spelling of 1211957354161 in words is "one trillion, two hundred eleven billion, nine hundred fifty-seven million, three hundred fifty-four thousand, one hundred sixty-one".