2154105221 has 4 divisors (see below), whose sum is σ = 2267479200. Its totient is φ = 2040731244.

The previous prime is 2154105203. The next prime is 2154105251. The reversal of 2154105221 is 1225014512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2154105221 - 2¹⁴ = 2154088837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2154105251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56686961 + ... + 56686998.

It is an arithmetic number, because the mean of its divisors is an integer number (566869800).

Almost surely, 2^2154105221 is an apocalyptic number.

It is an amenable number.

2154105221 is a deficient number, since it is larger than the sum of its proper divisors (113373979).

2154105221 is a wasteful number, since it uses less digits than its factorization.

2154105221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113373978.

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 2154105221 is about 46412.3391028722. The cubic root of 2154105221 is about 1291.4838244933.

Adding to 2154105221 its reverse (1225014512), we get a palindrome (3379119733).

The spelling of 2154105221 in words is "two billion, one hundred fifty-four million, one hundred five thousand, two hundred twenty-one".