2156121 has 24 divisors (see below), whose sum is σ = 3519360. Its totient is φ = 1260000.

The previous prime is 2156117. The next prime is 2156123. The reversal of 2156121 is 1216512.

It is not a de Polignac number, because 2156121 - 2² = 2156117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2156094 and 2156103.

It is not an unprimeable number, because it can be changed into a prime (2156123) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2496 + ... + 3246.

It is an arithmetic number, because the mean of its divisors is an integer number (146640).

2^2156121 is an apocalyptic number.

It is an amenable number.

2156121 is a deficient number, since it is larger than the sum of its proper divisors (1363239).

2156121 is a wasteful number, since it uses less digits than its factorization.

2156121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 797 (or 794 counting only the distinct ones).

The product of its digits is 120, while the sum is 18.

The square root of 2156121 is about 1468.3735900649. The cubic root of 2156121 is about 129.1886549224.

It can be divided in two parts, 215 and 6121, that added together give a palindrome (6336).

The spelling of 2156121 in words is "two million, one hundred fifty-six thousand, one hundred twenty-one".