2153921 has 12 divisors (see below), whose sum is σ = 2706816. Its totient is φ = 1677720.

The previous prime is 2153909. The next prime is 2153929. The reversal of 2153921 is 1293512.

It is a de Polignac number, because none of the positive numbers 2^k-2153921 is a prime.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (2153929) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 425 + ... + 2118.

It is an arithmetic number, because the mean of its divisors is an integer number (225568).

2^2153921 is an apocalyptic number.

It is an amenable number.

2153921 is a deficient number, since it is larger than the sum of its proper divisors (552895).

2153921 is a wasteful number, since it uses less digits than its factorization.

2153921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2572 (or 2561 counting only the distinct ones).

The product of its digits is 540, while the sum is 23.

The square root of 2153921 is about 1467.6242707178. The cubic root of 2153921 is about 129.1447007161.

The spelling of 2153921 in words is "two million, one hundred fifty-three thousand, nine hundred twenty-one".