2155542121 has 8 divisors (see below), whose sum is σ = 2183539680. Its totient is φ = 2127592992.

The previous prime is 2155542119. The next prime is 2155542133. The reversal of 2155542121 is 1212455512.

2155542121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 2155542121 - 2¹ = 2155542119 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2155542121.

It is not an unprimeable number, because it can be changed into a prime (2155542721) 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, 82206 + ... + 105208.

It is an arithmetic number, because the mean of its divisors is an integer number (272942460).

Almost surely, 2^2155542121 is an apocalyptic number.

It is an amenable number.

2155542121 is a deficient number, since it is larger than the sum of its proper divisors (27997559).

2155542121 is a wasteful number, since it uses less digits than its factorization.

2155542121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24215.

The product of its digits is 4000, while the sum is 28.

The square root of 2155542121 is about 46427.8162419901. The cubic root of 2155542121 is about 1291.7709229165.

Adding to 2155542121 its reverse (1212455512), we get a palindrome (3367997633).

The spelling of 2155542121 in words is "two billion, one hundred fifty-five million, five hundred forty-two thousand, one hundred twenty-one".